Steven Doerr, MD, is a U.S. board-certified Emergency Medicine Physician. Dr. Doerr received his undergraduate degree in Spanish from the University of Colorado at Boulder. He graduated with his Medical Degree from the University Of Colorado Health Sciences Center in Denver, Colorado in 1998 and completed his residency training in Emergency Medicine from Denver Health Medical Center in Denver, Colorado in 2002, where he also served as Chief Resident.
Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.
Travelers to other countries often face health issues
they wouldn't ordinarily experience at home. To minimize your risks of becoming
seriously ill when traveling abroad, you should find out in advance whether any
specific immunizations may be recommended for travel to the region of the world
you'll be visiting. It's also a good time to review your own immunization
history.
According to the U.S. Centers for Disease Control and Prevention (CDC), it's best to
schedule a visit to your doctor or travel medicine clinic 4-6 weeks before an
international trip. Since your body needs time to build up immunity after
receiving a vaccine and many vaccines are given in a series over time,
getting an early start on your immunizations is the best way to protect
yourself. Even if you are making a last-minute trip or plan to leave in less
than four weeks, you should still check with your doctor to see if any vaccines
or preventive medications might be recommended.
The CDC divides travel vaccinations into three categories: routine,
recommended, and required. The only vaccine classified as "required" by
International Health Regulations is the yellow fever vaccination for travel to
certain countries in sub-Saharan Africa and tropical South America.
What is yellow fever? What is the history of yellow fever?
Yellow fever is an acute viral infectious disease that is transmitted to
humans through the bite of infected mosquitoes. Though many cases of yellow
fever are mild and self-limiting, yellow fever can also be a life-threatening
disease causing hemorrhagic fever and
hepatitis (hence the term "yellow" from
the jaundice it can cause). This viral disease occurs in tropical areas of
Africa and South America, and each year there are an estimated 200,000 cases of
yellow fever worldwide, leading to approximately 30,000 deaths. An increase in
the number of cases of yellow fever in the last few decades has led to campaigns
aimed at improving public awareness and disease prevention for this re-emerging
infectious disease.
Yellow fever is thought to have originated in Africa and was likely brought
to the Americas on ships during the slave trade. Several significant yellow
fever outbreaks have occurred throughout history, with the first documented
outbreak occurring in the Yucatan peninsula during the 17th century. During the
late 18th century, a severe yellow fever outbreak struck New England and several
North American port cities. The city of Philadelphia is though to have lost
about one-tenth of its population during the 1793 yellow fever epidemic, causing
many notable figures in American politics to flee the city. The last major
yellow fever outbreak in North America occurred in New Orleans in 1905.
The theory that yellow fever is transmitted by a mosquito was first
introduced by a Cuban physician, Dr. Carlos Finlay, in the late 19th century. It
was not until 1900, using earlier research from Dr. Finlay as a foundation, that
U.S. Army Major Dr. Walter Reed and his team proved that yellow fever was in fact
transmitted by mosquitoes. This groundbreaking idea was instrumental in leading
to the subsequent control of yellow fever in various regions. The virus
responsible for yellow fever was later isolated in the late 1920s, and this
breakthrough discovery allowed Max Theiler to later develop the first
vaccine
against yellow fever in the 1930s. This successful vaccine helped control and
eliminate yellow fever from various countries in Africa and South America during
the mid 20th century.
What causes yellow fever?
Yellow fever is caused by a virus. The yellow fever virus is a
single-stranded RNA virus that belongs to the Flavivirus genus. After
transmission of the virus occurs, it replicates in regional lymph nodes and
subsequently spreads via the bloodstream. This widespread dissemination can
affect the bone marrow, spleen, lymph nodes, kidneys, and liver, in addition to
other organs. Tissue damage to the liver, for example, can lead to jaundice and
disrupt the body's blood-clotting mechanism, leading to the hemorrhagic
complications sometimes seen with yellow fever.
This picture shows multiple
virions of the yellow fever virus. Source: CDC
Abdominal pain is pain in the belly and can be acute or chronic. Causes include inflammation, distention of an organ, and loss of the blood supply to an organ. Abdominal pain can reflect a major problem with one of the organs in the abdomen such as the appendix, gallbladder, large and small intestine, pancreas, liver, colon, duodenum, and spleen.
Rectal bleeding (hematochezia) refers to the passage of bright red blood from the anus. Rectal bleeding may be moderate to severe and most bleeding comes from the colon, rectum, or anus. Common causes include anal fissures, hemorrhoids, diverticulitis, and more.
Kidney failure can occur from an acute event or a chronic condition or disease. Prerenal kidney failure is caused by blood loss, dehydration, medication. Some of the renal causes of kidney failure are from sepsis, medications, rhabdomyolysis, multiple myeloma, and acute glomerulonephritis. Post renal causes of kidney failure include bladder obstruction, prostate problems, tumors, or kidney stones. Treatment options included diet, medications, or dialysis.
Headaches can be divided into two categories: primary headaches and secondary headaches. Migraine headaches, tension headaches, and cluster headaches are considered primary headaches. Secondary headaches are caused by disease. Headache symptoms vary with the headache type. Over-the-counter pain relievers provide short-term relief for most headaches.
Nosebleed is common in dry climates during winter months, and in hot dry climates with low humidity. Individual taking blood clotting medications, aspirin, or antiinflammatory medications may be more prone to nose bleeding. Other factors that contribute to nosebleed are trauma (including nose picking), rhinitis, and high blood pressure. Treatment depends on the severity of the condition.
Jaundice is a yellowish staining of the skin and whites of the eyes (sclerae) with bilirubin, the pigment found in bile. Jaundice can be an indicator of liver or gallbladder disease, or it may result from the rupture of red blood cells (hemolysis).
Nausea is an uneasiness of the stomach that often precedes vomiting. Nausea and vomiting are not diseases, but they are symptoms of many conditions. The causes of vomiting differ according to age, and treatment depends upon the cause of nausea and vomiting.
Although a fever technically is any body temperature above the normal of 98.6 degrees F. (37 degrees C.), in practice a person is usually not considered to have a significant fever until the temperature is above 100.4 degrees F (38 degrees C.). Fever is part of the body's own disease-fighting arsenal: rising body temperatures apparently are capable of killing off many disease- producing organisms.
Epilepsy is a brain disorder in which the person has seizures. There are two kinds of seizures, focal and generalized. There are many causes of epilepsy. Treatment of epilepsy (seizures) depends upon the cause and type of seizures experienced.
A bruise, or contusion, is caused when blood vessels are damaged or broken as the result of a blow to the skin. The raised area of a bump or bruise results from blood leaking from these injured blood vessels into the tissues as well as from the body's response to the injury. Treatments include applying an ice pack and pressure to the area by hand.
Coma is the inability to waken or react to the surrounding environment. The Glasgow Coma Scale is frequently used to measure the depth of coma. Causes of coma include trauma, bleeding, edema, lack of oxygen, poisoning, or hypoglycemia. Prognosis for a patient in a coma depends on the cause of the coma.
Bug bites and stings have been known to transmit insect-borne illnesses such as West Nile virus, Rocky Mountain spotted fever, and Lyme disease. Though most reactions to insect bites and stings are mild, some reactions may be life-threatening. Preventing bug bites and stings with insect repellant, wearing the proper protective attire, and not wearing heavily scented perfumes when in grassy, wooded, and brushy areas is key.
Travelers should prepare for their trip by visiting their physician to get the proper vaccinations and obtain the necessary medication if they have a medical condition or chronic disease. Diseases that travelers may pick up from contaminated water or food, insect or animal bites, or from other people include malaria, meningococcal meningitis, yellow fever, hepatitis A, typhoid fever, polio, and cholera.
Abdominal pain is pain that is felt in the abdomen. The abdomen is an anatomical area that is bounded by the lower margin of the ribs and diaphragm above, the pelvic bone (pubic ramus) below, and the flanks on each side. Although abdominal pain can arise from the tissues of the abdominal wall that surround the abdominal cavity (such as the skin and abdominal wall muscles), the term abdominal pain generally is used to describe pain originating from organs within the abdominal cavity. Organs of the abdomen include the stomach, small intestine, colon, liver, gallbladder,
spleen, and pancreas.
Occasionally, pain may be felt in the abdomen even though it is arising from organs that are close to, but not within, the abdominal cavity. For example, conditions of the lower lungs, the kidneys, and the uterus or ovaries can cause abdominal pain. On the other hand, it also is possible for pain from organs within the abdomen to be felt outside of the ab...