Major infectious diseases

This entry lists major infectious diseases likely to be encountered in countries where the risk of such diseases is assessed to be very high as compared to the United States. These infectious diseases represent risks to US Government personnel traveling to the specified country for a period of less than three years. The degree of risk is assessed by considering the foreign nature of these infectious diseases, their severity, and the probability of being affected by the diseases present. The diseases listed do not necessarily represent the total disease burden experienced by the local population.
The risk to an individual traveler varies considerably by the specific location, visit duration, type of activities, type of accommodations, time of year, and other factors. Consultation with a travel medicine physician is needed to evaluate individual risk and recommend appropriate preventive measures such as vaccines.
Diseases are organized into the following six exposure categories shown in italics and listed in typical descending order of risk. Note: The sequence of exposure categories listed in individual country entries may vary according to local conditions.

food or waterborne diseases acquired through eating or drinking:
Hepatitis A - viral disease that interferes with the functioning of the liver; spread through consumption of food or water contaminated with fecal matter, principally in areas of poor sanitation; victims exhibit fever, jaundice, and diarrhea; 15% of victims will experience prolonged symptoms over 6-9 months; vaccine available.
Hepatitis E - water-borne viral disease that interferes with the functioning of the liver; most commonly spread through fecal contamination of drinking water; victims exhibit jaundice, fatigue, abdominal pain, and dark colored urine.
Typhoid fever - bacterial disease spread through contact with food or water contaminated by fecal matter or sewage; victims exhibit sustained high fevers; left untreated, mortality rates can reach 20%.

vector-borne diseases acquired through the bite of an infected arthropod:
Malaria - caused by single-cell parasitic protozoa Plasmodium; transmitted to humans via the bite of the female Anopheles mosquito; parasites multiply in the liver attacking red blood cells resulting in cycles of fever, chills, and sweats accompanied by anemia; death due to damage to vital organs and interruption of blood supply to the brain; endemic in 85, mostly tropical, countries with 95% of cases and the majority of 0.4-0.6 million estimated annual deaths occurring in sub-Saharan Africa (six countries – Nigeria, the Democratic Republic of the Congo, Uganda, Mozambique, Angola and Burkina Faso – accounted for just over half of all malaria deaths globally in 2020).
Dengue fever - mosquito-borne (Aedes aegypti) viral disease associated with urban environments; manifests as sudden onset of fever and severe headache; occasionally produces shock and hemorrhage leading to death in 5% of cases.
Yellow fever - mosquito-borne (in urban areas Aedes aegypti) viral disease associated with urban environments; severity ranges from influenza-like symptoms to severe hepatitis and hemorrhagic fever; occurs only in tropical South America and sub-Saharan Africa, where most cases are reported; fatality rate is less than 20%.
Japanese Encephalitis - mosquito-borne (Culex tritaeniorhynchus) viral disease associated with rural areas in Asia; acute encephalitis can progress to paralysis, coma, and death; fatality rates 30%.
African Trypanosomiasis - caused by the parasitic protozoa Trypanosoma; transmitted to humans via the bite of bloodsucking tsetse flies; infection leads to malaise and irregular fevers and, in advanced cases when the parasites invade the central nervous system, coma and death; endemic in 36 countries of sub-Saharan Africa; cattle and wild animals act as reservoir hosts for the parasites.
Cutaneous Leishmaniasis - caused by the parasitic protozoa leishmania; transmitted to humans via the bite of sandflies; results in skin lesions that may become chronic; endemic in 88 countries; 90% of cases occur in Iran, Afghanistan, Syria, Saudi Arabia, Brazil, and Peru; wild and domesticated animals as well as humans can act as reservoirs of infection.
Plague - bacterial disease transmitted by fleas normally associated with rats; person-to-person airborne transmission also possible; recent plague epidemics occurred in areas of Asia, Africa, and South America associated with rural areas or small towns and villages; manifests as fever, headache, and painfully swollen lymph nodes; disease progresses rapidly and without antibiotic treatment leads to pneumonic form with a death rate in excess of 50%.
Crimean-Congo hemorrhagic fever - tick-borne viral disease; infection may also result from exposure to infected animal blood or tissue; geographic distribution includes Africa, Asia, the Middle East, and Eastern Europe; sudden onset of fever, headache, and muscle aches followed by hemorrhaging in the bowels, urine, nose, and gums; mortality rate is approximately 30%.
Rift Valley fever - viral disease affecting domesticated animals and humans; transmission is by mosquito and other biting insects; infection may also occur through handling of infected meat or contact with blood; geographic distribution includes eastern and southern Africa where cattle and sheep are raised; symptoms are generally mild with fever and some liver abnormalities, but the disease may progress to hemorrhagic fever, encephalitis, or ocular disease; fatality rates are low at about 1% of cases.
Chikungunya - mosquito-borne (Aedes aegypti) viral disease associated with urban environments, similar to Dengue Fever; characterized by sudden onset of fever, rash, and severe joint pain usually lasting 3-7 days, some cases result in persistent arthritis.
Severe fever with thrombocytopenia syndrome (SFTS) - a tick-borne viral (phlebovirus) hemorrhagic fever; infection can spread through contact with infected wild and domesticated animals, including household pets; human-to-human transmission is also possible through direct contact with infected blood or bodily secretions; disease is characterized by rapid-onset of acute fever, vomiting, diarrhea, thrombocytopenia (low platelet count), low white cell count, bleeding tendency, and multiple organ failure; mortality rate is between 10-40%; there is no vaccine or treatment for the disease
Bartonellosis (Oroya fever) – a parasitic bacterial (Bartonella bacilliformis) infection transmitted by bites from infected sand flies (genus Lutzomyia); also known as Carrion’s disease; the bacteria is limited to the Andes Mountains of western South America at an elevation of 915-3,050 m (3,000 to 10,000 ft.) and chiefly in  Peru (where most cases are reported), Colombia, and Ecuador; Oroya fever is the acute phase of the disease and characterized by fever, headache, muscle aches, abdominal pain, and severe anemia may occur; complications can occur in up to 70% of patients with Oroya fever, including secondary infections and cardiopulmonary complications such as heart failure, pericardial effusion, pulmonary edema, and cardiogenic shock; infection with B. bacilliformis requires antibiotic treatment
Hantaviral hemorrhagic fever with renal syndrome (HFRS), also known as Korean hemorrhagic fever - hantaviruses are carried and transmitted by rodents through exposure to aerosolized urine, droppings, or saliva of infected rodents or after exposure to dust from their nests; transmission may also occur when infected urine or other materials are directly introduced into broken skin or onto the mucous membranes of the eyes, nose, or mouth; human-to-human transmission is rare; the most serious disease is caused by the Hantaan or Seoul  viruses; symptoms of HFRS usually develop within 1 to 2 weeks after exposure to infectious material but, in rare cases, may take up to 8 weeks to develop; initial symptoms begin suddenly and include intense headaches, back and abdominal pain, fever, chills, nausea, and blurred vision; later symptoms can include low blood pressure, acute shock, vascular leakage, and acute kidney failure, which can cause severe fluid overload; fatality ranges from 5-15% for the most serious cases of HFRS caused by Hantaan virus; there is no cure for HFRS, treatment involves supportive therapy including renal dialysis; vaccines are available

water-contact diseases acquired through swimming or wading in freshwater lakes, streams, and rivers:
Leptospirosis - bacterial disease that affects animals and humans; infection occurs through contact with water, food, or soil contaminated by animal urine; symptoms include high fever, severe headache, vomiting, jaundice, and diarrhea; untreated, the disease can result in kidney damage, liver failure, meningitis, or respiratory distress; fatality rates are low but left untreated recovery can take months.
Schistosomiasis - caused by parasitic trematode flatworm Schistosoma; fresh water snails act as intermediate host and release larval form of parasite that penetrates the skin of people exposed to contaminated water; worms mature and reproduce in the blood vessels, liver, kidneys, and intestines releasing eggs, which become trapped in tissues triggering an immune response; may manifest as either urinary or intestinal disease resulting in decreased work or learning capacity; mortality, while generally low, may occur in advanced cases usually due to bladder cancer; endemic in 74 developing countries with 80% of infected people living in sub-Saharan Africa; humans act as the reservoir for this parasite.

aerosolized dust or soil-contact disease acquired through inhalation of aerosols contaminated with rodent urine:
Lassa fever - viral disease carried by rats of the genus Mastomys; endemic in portions of West Africa; infection occurs through direct contact with or consumption of food contaminated by rodent urine or fecal matter containing virus particles; fatality rate can reach 50% in epidemic outbreaks.

respiratory disease acquired through close contact with an infectious person:
Meningococcal meningitis - bacterial disease causing an inflammation of the lining of the brain and spinal cord; one of the most important bacterial pathogens is Neisseria meningitidis because of its potential to cause epidemics; symptoms include stiff neck, high fever, headaches, and vomiting; bacteria are transmitted from person to person by respiratory droplets and facilitated by close and prolonged contact resulting from crowded living conditions, often with a seasonal distribution; death occurs in 5-15% of cases, typically within 24-48 hours of onset of symptoms; highest burden of meningococcal disease occurs in the hyperendemic region of sub-Saharan Africa known as the "Meningitis Belt" which stretches from Senegal east to Ethiopia.

animal-contact disease acquired through direct contact with local animals:
Rabies - viral disease of mammals usually transmitted through the bite of an infected animal, most commonly dogs; virus affects the central nervous system causing brain alteration and death; symptoms initially are non-specific fever and headache progressing to neurological symptoms; death occurs within days of the onset of symptoms.

• Afghanistan

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: Crimea-Congo hemorrhagic fever, malaria
  
  note: Afghanistan is one of two countries with endemic wild polio virus (the other is Pakistan) and considered high risk for international spread of the disease; before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the US Centers for Disease Control and Prevention (CDC) recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Algeria

  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Algeria is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Angola

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, typhoid fever
  
  vectorborne diseases: dengue fever, malaria
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies

• Bangladesh

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria are high risks in some locations
  
  water contact diseases: leptospirosis
  
  animal contact diseases: rabies

• Benin

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Benin is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Bolivia

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea and hepatitis A
  
  vectorborne diseases: dengue fever and malaria

• Botswana

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Botswana is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Brazil

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea and hepatitis A
  
  vectorborne diseases: dengue fever and malaria
  
  water contact diseases: schistosomiasis

• Burkina Faso

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Burkina Faso is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Burma

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever, malaria, and Japanese encephalitis
  
  animal contact diseases: rabies

• Burundi

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Burundi is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Cambodia

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever, Japanese encephalitis, and malaria

• Cameroon

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Cameroon is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Canada

  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in North America; Canada is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Central African Republic

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; the Central African Republic is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Chad

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Chad is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• China

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: Crimean-Congo hemorrhagic fever, dengue fever, Japanese encephalitis, severe fever thrombocytopenia syndrome (SFTS)
  
  soil contact diseases: hantaviral hemorrhagic fever with renal syndrome (HFRS)

• Colombia

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: dengue fever and malaria

• Congo, Democratic Republic of the

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria, dengue fever, and trypanosomiasis-gambiense (African sleeping sickness)
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; the Democratic Republic of the Congo is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Congo, Republic of the

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; the Republic of the Congo is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Cook Islands

  degree of risk: high (2020)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: malaria

• Costa Rica

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: dengue fever
  
  note: on 17 April 2023, the Centers for Disease Control and Prevention (CDC) issued a Travel Alert for an outbreak of Plasmodium falciparum malaria in the province of Limón, Costa Rica; there is also malaria transmission in Alajuela Province; public health authorities in Costa Rica are responding to this outbreak by enhancing malaria surveillance; CDC now recommends malaria chemoprohylaxis for travelers visiting Limón and Alajuela Provinces in Costa Rica prior to travel; the parasite P. falciparum, which is found worldwide in tropical and subtropical areas is spread through the bite of female mosquitoes of the genus Anopheles; P. falciparum can cause severe malaria because it multiples rapidly in the blood, and can thus cause severe blood loss (anemia); in addition, the infected parasites can clog small blood vessels; when this occurs in the brain, cerebral malaria results, a complication that can be fatal; seek medical care if you develop fever, chills, sweats, headache, vomiting, or body aches; malaria is a medical emergency, and appropriate treatment should not be delayed (see attached map)

• Cote d'Ivoire

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Côte d'Ivoire is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Croatia

  degree of risk: intermediate (2023)
  
  vectorborne diseases: tickborne encephalitis

• Cuba

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea and hepatitis A
  
  vectorborne diseases: dengue fever

• Djibouti

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Djibouti is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Dominican Republic

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever

• Ecuador

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria

• Egypt

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever

• El Salvador

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea
  
  vectorborne diseases: dengue fever

• Equatorial Guinea

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  animal contact diseases: rabies
  
  note: on 27 March 2023, the Centers for Disease Control and Prevention (CDC) issued a Travel Alert for Equatorial Guinea for an outbreak of Marburg virus disease; Marburg is a viral hemorrhagic fever spread by contact with blood or body fluids of a person infected with or who has died from Marburg; it is also spread by contact with contaminated objects (such as clothing, bedding, needles, and medical equipment) or by contact with animals, such as bats and nonhuman primates, who are infected with Marburg virus; infection with Marburg virus is often fatal and there are no approved vaccines or treatments for Marburg; avoid non-essential travel to the provinces where the outbreak is occurring; watch your health for symptoms of Marburg while in the outbreak area and for 21 days after leaving the outbreak area; consult the Centers for Disease Control and Prevention (CDC) Travel Health Notices for additional guidance (see attached map)

• Eritrea

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Eritrea is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Estonia

  degree of risk: intermediate (2020)
  
  vectorborne diseases: tickborne encephalitis

• Eswatini

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria
  
  water contact diseases: schistosomiasis

• Ethiopia

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Ethiopia is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Gabon

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies

• Gambia, The

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; The Gambia is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Gaza Strip

  note: on 21 March 2022, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Asia; the Gaza Strip is currently considered a high risk to travelers for polio; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Ghana

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Ghana is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Guatemala

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria

• Guinea

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  aerosolized dust or soil contact diseases: Lassa fever (2016)

• Guinea-Bissau

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies

• Guyana

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria

• Haiti

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria

• Honduras

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever

• Hungary

  degree of risk: intermediate (2016)
  
  vectorborne diseases: tickborne encephalitis (2016)

• India

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: dengue fever, Crimean-Congo hemorrhagic fever, Japanese encephalitis, and malaria
  
  water contact diseases: leptospirosis
  
  animal contact diseases: rabies

• Indonesia

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Southeast Asia; Indonesia is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Iran

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: Crimean-Congo hemorrhagic fever

• Iraq

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever

• Israel

  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Asia; Israel is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Kenya

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria, dengue fever, and Rift Valley fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies

• Laos

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria

• Latvia

  degree of risk: intermediate (2023)
  
  vectorborne diseases: tickborne encephalitis

• Lesotho

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever

• Liberia

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  aerosolized dust or soil contact diseases: Lassa fever
  
  note: on 21 March 2022, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Liberia is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Lithuania

  degree of risk: intermediate (2023)
  
  vectorborne diseases: tickborne encephalitis

• Madagascar

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Madagascar is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Malawi

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Malawi is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Malaysia

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: dengue fever
  
  water contact diseases: leptospirosis

• Mali

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  aerosolized dust or soil contact diseases: Lassa fever
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Mali is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Mauritania

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 21 March 2022, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Mauritania is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Mexico

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea and hepatitis A
  
  vectorborne diseases: dengue fever

• Montenegro

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: Crimean-Congo hemorrhagic fever

• Mozambique

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Mozambique is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Namibia

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria
  
  water contact diseases: schistosomiasis

• Nepal

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: Japanese encephalitis, malaria, and dengue fever

• Nicaragua

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria

• Niger

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Niger is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Nigeria

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: malaria, dengue fever, and yellow fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  aerosolized dust or soil contact diseases: Lassa fever
  
  note 1: on 4 May 2022, the Centers for Disease Control and Prevention issued a Travel Health Notice for a Yellow Fever outbreak in Nigeria; a large, ongoing outbreak of yellow fever in Nigeria began in September 2017; the outbreak is now spread throughout the country with the Nigerian Ministry of Health reporting cases of the disease in multiple states (Bauchi, Benue, Delta, Ebonyi, and Enugu); the CDC recommends travelers going to Nigeria should receive vaccination against yellow fever at least 10 days before travel and should take steps to prevent mosquito bites while there; those never vaccinated against yellow fever should avoid travel to Nigeria during the outbreak (see attached map)
  
  note 2: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Nigeria is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine
  note 3: on 24 February 2023, the Centers for Disease Control and Prevention issued a Travel Health Alert for a diphtheria outbreak in several states in Nigeria; vaccination against diphtheria is essential to protect against disease; if you are traveling to an affected area, you should be up to date with your diphtheria vaccines; before travel, discuss the need for a booster dose with your healthcare professional; diphtheria is a serious infection caused by strains of Corynebacterium diphtheriae bacteria that make a toxin from which people get very sick; diphtheria bacteria spread from person to person through respiratory droplets like from coughing or sneezing; people can also get sick from touching open sores or ulcers of people sick with diphtheria (see attached map)

• Pakistan

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: dengue fever, malaria, and Crimean-Congo hemorrhagic fever
  
  animal contact diseases: rabies
  
  note: Pakistan is one of two countries with endemic wild polio virus (the other is Afghanistan) and considered high risk for international spread of the disease; before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the US Centers for Disease Control and Prevention (CDC) recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Panama

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: dengue fever

• Papua New Guinea

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria

• Paraguay

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever

• Peru

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever, malaria, and Bartonellosis (Oroya fever)

• Philippines

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria
  
  water contact diseases: leptospirosis

• Pitcairn Islands

  degree of risk: high (2020)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: malaria

• Poland

  degree of risk: intermediate (2023)
  
  vectorborne diseases: tickborne encephalitis

• Russia

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: Crimean-Congo hemorrhagic fever, tickborne encephalitis

• Rwanda

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  animal contact diseases: rabies

• Sao Tome and Principe

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis

• Senegal

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Senegal is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Serbia

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: Crimean-Congo hemorrhagic fever

• Sierra Leone

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  aerosolized dust or soil contact diseases: Lassa fever
  
  note: on 21 March 2022, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Sierra Leone is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Somalia

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: dengue fever, malaria, and Rift Valley fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Somalia is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• South Africa

  degree of risk: intermediate (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  water contact diseases: schistosomiasis

• South Sudan

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: malaria, dengue fever, Trypanosomiasis-Gambiense (African sleeping sickness)
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis

• Sri Lanka

  degree of risk: intermediate (2023)
  
  vectorborne diseases: dengue fever
  
  water contact diseases: leptospirosis
  
  animal contact diseases: rabies

• Sudan

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: malaria, dengue fever, and Rift Valley fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Sudan is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Suriname

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria

• Tajikistan

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever

• Tanzania

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria, dengue fever, and Rift Valley fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies

• Thailand

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea
  
  vectorborne diseases: dengue fever, Japanese encephalitis, and malaria

• Timor-Leste

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria

• Togo

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  respiratory diseases: meningococcal meningitis
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Togo is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Uganda

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A and E, and typhoid fever
  
  vectorborne diseases: malaria, dengue fever, and Trypanosomiasis-Gambiense (African sleeping sickness)
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  note: on 15 November 2022, the US Centers for Disease Control and Prevention (CDC) issued an updated Level Two Travel Alert (Practice Enhanced Precautions) for Ebola virus in Uganda, currently present in the following districts: Mubende, Kyegegwa, Kassanda, Kagadi, Bunyangabu, Kampala, Wakiso, Masaka City, and Jinja, and recommended that people avoid non-essential travel to these regions; this outbreak has been linked to the Sudan ebolavirus for which there are no vaccines or therapeutics approved for prevention or treatment of the Sudan ebolavirus; in addition, on 6 October 2022, the State Department issued a Level Three Travel Advisory to reconsider travel to Uganda and also announced the following "The Department of Homeland Security (DHS) and the CDC announced entrance screening for travelers who have been in Uganda in the last 21 days.  All U.S.-bound passengers who have been in Uganda at any point in the 21 days prior to their arrival will be routed to one of the following designated airports: New York (JFK), Newark (EWR), Atlanta (ATL), Chicago (ORD), or Washington (IAD), where they will undergo enhanced screening, including a health questionnaire and temperature checks. This applies to all passengers, including U.S. citizens, lawful permanent residents, and foreign nationals (to include Diplomatic and Official visas)."

• United Kingdom

  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued an updated Travel Alert for polio in Europe; the United Kingdom is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Venezuela

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea and hepatitis A
  
  vectorborne diseases: dengue fever and malaria
  
  note: as of 30 September 2021, the Centers for Disease Control and Prevention recommends that travelers avoid all nonessential travel to Venezuela; the country is experiencing outbreaks of infectious diseases, and adequate health care is currently not available in most of the country; there are shortages of food, water, electricity, medicine, and medical supplies that have contributed to an increasing humanitarian crisis affecting much of the country

• Vietnam

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever, malaria, and Japanese encephalitis

• West Bank

  note: on 21 March 2022, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Asia; the West Bank is currently considered a high risk to travelers for polio; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• World

  food or waterborne diseases: Typhoid fever - An estimated 26 million cases of typhoid fever and 5 million cases of paratyphoid fever occur worldwide each year, causing 215,000 deaths. High-risk regions for typhoid and paratyphoid fever include Africa and Southeast Asia; lower-risk regions include East Asia, South America, and the Caribbean. Typhoid fever is a life-threatening illness caused by Salmonella Typhi bacteria. Paratyphoid fever is a life-threatening illness caused by Salmonella Paratyphi bacteria. The bacteria that cause typhoid fever are most often spread through contaminated food and water and person to person contact. Symptoms of typhoid fever include high fever, weakness, stomach pain, headache, constipation or diarrhea, cough, and loss of appetite. Typhoid fever can be fatal without appropriate antibiotic treatment. CDC recommends that all travelers (even short-term travelers) to affected areas be vaccinated against typhoid fever before travel.
  
  vectorborne diseases: Malaria - In 2020, an estimated 627,000 people died of malaria—most were young children in sub-Saharan Africa. Nearly half the world’s population lives in areas at risk of malaria transmission in 87 countries and territories (see attached map). In 2020, malaria caused an estimated 241 million clinical episodes, and 627,000 deaths. An estimated 95% of deaths in 2020 were in the WHO African Region. The predominant parasite species is Plasmodium falciparum, which is the species that is most likely to cause severe malaria and death. Where malaria is found depends mainly on climatic factors such as temperature, humidity, and rainfall. Malaria is transmitted in tropical and subtropical areas, where Anopheles mosquitoes can survive and multiply, and malaria parasites can complete their growth cycle in the mosquitoes (“extrinsic incubation period”). Temperature is particularly critical. For example, at temperatures below 20°C (68°F), Plasmodium falciparum (which causes severe malaria) cannot complete its growth cycle in the Anopheles mosquito, and thus cannot be transmitted.
  African Trypanosomiasis - also known as “sleeping sickness”, is caused by microscopic parasites of the species Trypanosoma brucei. It is transmitted by the tsetse fly (Glossina species), which is found only in sub-Saharan Africa. Two morphologically indistinguishable subspecies of the parasite cause distinct disease patterns in humans: T. b. gambiense causes a slowly progressing African trypanosomiasis in western and central Africa and T. b. rhodesiense causes a more acute African trypanosomiasis in eastern and southern Africa. Control efforts have reduced the number of annual cases and for the first time in 50 years, the number of reported cases fell under 10,000 in 2009. In 2017–2018, fewer than 2000 cases were reported to WHO. The number of cases continue to drop and in 2020, fewer than 700 combined cases were reported to WHO; over 85% caused by T. b. gambiense and around 15% caused by T. b. rhodesiense. Sleeping sickness is curable with medication but is fatal if left untreated.
  Dengue fever - Dengue viruses are spread to people through the bite of an infected Aedes species (Ae. aegypti or Ae. albopictus) mosquito. Almost half of the world’s population, about 4 billion people, live in areas with a risk of dengue. Dengue is often a leading cause of illness in areas with risk. Each year, up to 400 million people get infected with dengue. Approximately 100 million people get sick from infection, and 40,000 die from severe dengue. Dengue has emerged as a worldwide problem since the 1960s. The disease is common in many popular tourist destinations in the Caribbean (including Puerto Rico), Central and South America, Southeast Asia, and the Pacific Islands (see attached regional maps). In the United States, local cases and limited spread of dengue does occur periodically in some states with hot, humid climates and Aedes mosquitoes.
  
  water contact diseases: Schistosomaisis - also known as bilharzia, is a disease caused by parasitic worms. In terms of impact this disease is second only to malaria as the most devastating parasitic disease (see attached map).  Schistosomiasis is considered one of the neglected tropical diseases (NTDs). The parasites that cause schistosomiasis live in certain types of freshwater snails. The infectious form of the parasite, known as cercariae, emerge from the snail into the water. You can become infected when your skin comes in contact with contaminated freshwater. Most human infections are caused by Schistosoma mansoni, S. haematobium, or S. japonicum. Freshwater becomes contaminated by Schistosoma eggs when infected people urinate or defecate in the water. The eggs hatch, and if certain types of freshwater snails are present in the water, the parasites develop and multiply inside the snails. The parasite leaves the snail and enters the water where it can survive for about 48 hours. Schistosoma parasites can penetrate the skin of persons who are wading, swimming, bathing, or washing in contaminated water.
  
  respiratory diseases: Meningococcal meningitis - Meningococcal disease occurs worldwide, with the highest incidence of disease found in the ‘meningitis belt’ of sub-Saharan Africa (see attached map). In this region, major epidemics occur every 5 to 12 years with attack rates reaching 1,000 cases per 100,000 population. Bacteria called Neisseria meningitidis cause meningococcal disease. About 1 in 10 people have these bacteria in the back of their nose and throat without being ill. This is called being ‘a carrier.’ Sometimes the bacteria invade the body and cause certain illnesses, which are known as meningococcal disease. Other regions of the world experience lower overall rates of disease and occasional outbreaks. Annual attack rates in these regions averages around 0.3 to 3 per 100,000 population. Risk factors for meningococcal disease outbreaks in Africa are not fully understood. However, the following characteristics create favorable conditions for meningococcal disease epidemics: Dry and dusty conditions during the dry season between December to June, Immunological susceptibility of the population, Travel and large population displacements, Crowded living conditions
  
  note 1: widespread ongoing transmission of a respiratory illness caused by the novel coronavirus (COVID-19) is occurring globally; older adults and people of any age with serious chronic medical conditions are at increased risk for severe disease; as of 26 April 2023, 764,474,387 confirmed cases of COVID-19 and 6,915,286 deaths had been reported to the World Health Organization; as of 26 April 2023, 69.9% of the World population had received at least one dose of COVID-19 vaccine
  
  note 2: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for some international destinations (see attached map) currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Yemen

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: dengue fever and malaria
  
  water contact diseases: schistosomiasis
  
  note: on 21 March 2022, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Asia; Yemen is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Zambia

  degree of risk: very high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies
  
  note: on 22 March 2023, the US Centers for Disease Control and Prevention (CDC) issued a Travel Alert for polio in Africa; Zambia is currently considered a high risk to travelers for circulating vaccine-derived polioviruses (cVDPV); vaccine-derived poliovirus (VDPV) is a strain of the weakened poliovirus that was initially included in oral polio vaccine (OPV) and that has changed over time and behaves more like the wild or naturally occurring virus; this means it can be spread more easily to people who are unvaccinated against polio and who come in contact with the stool or respiratory secretions, such as from a sneeze, of an “infected” person who received oral polio vaccine; the CDC recommends that before any international travel, anyone unvaccinated, incompletely vaccinated, or with an unknown polio vaccination status should complete the routine polio vaccine series; before travel to any high-risk destination, the CDC recommends that adults who previously completed the full, routine polio vaccine series receive a single, lifetime booster dose of polio vaccine

• Zimbabwe

  degree of risk: high (2023)
  
  food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
  
  vectorborne diseases: malaria and dengue fever
  
  water contact diseases: schistosomiasis
  
  animal contact diseases: rabies