How do people get infected with Leishmania parasites?
The main route is through the bite of infected female phlebotomine sand flies. Sand flies become infected by sucking blood from an infected animal or person. People might not realize that sand flies are present because:
They do not make noise when they fly;
They are small: they are only about one-third the size of typical mosquitoes or even smaller;
Their bites might not be noticed (the bites may be painless or painful).
Sand flies usually are most active in twilight, evening, and night-time hours (from dusk to dawn). Although sand flies are less active during the hottest time of the day, they may bite if they are disturbed (for example, if a person brushes up against the trunk of a tree or other site where sand flies are resting).
Some types (species) of Leishmania parasites may also be spread by blood transfusions or contaminated needles (needle sharing). Congenital transmission (spread from a pregnant woman to her baby) has been reported.
Leishmaniasis is caused by a parasite that is spread to humans through the bite
of infected sand flies.
Leishmaniasis exists in many temperate and tropical
countries of the world. The disease is most common in India, Bangladesh, Nepal,
Sudan, Ethiopia, Afghanistan, Algeria, Iran, Saudi Arabia, Syria, Brazil,
Colombia, Peru, and Bolivia.
The most common type of leishmaniasis is cutaneous
leishmaniasis. This causes nodules or sores to form on the skin, including the
skin of the face. Affected people may have a single lesion or many lesions.
Sores heal slowly over months to years and leave scars.
Another type is called
visceral leishmaniasis. Parasites infect the tissues of key organs, especially
the liver, spleen, and bone marrow. Serious cases are usually fatal if not
treated.
Uncommonly, people who have had cutaneous leishmaniasis may get new
sores in the mucous membranes of the mouth, nose, and larynx even years after the
cutaneous leishmaniasis has resolved. This is called mucocutaneous leishmaniasis
and only occurs in limited areas of the New World.
Treatment consists of
medications that are specific to the type of leishmaniasis, the species of the
parasite, and to the country in which the disease was acquired.
Consultation
with the CDC and an infectious-disease consultant is strongly recommended for
assistance with diagnosis and treatment of cases imported into the United
States.
Those who work in or travel to affected areas can reduce their risk by
using insect repellents, protective clothing, and bed nets. These precautions are
especially important after dusk, because that is when the sand fly is most
active.
What is leishmaniasis?
Leishmaniasis is an infection caused by a parasite
that is spread to people through the bite of the female phlebotomine sand fly.
The parasite exists in many tropical and temperate countries. Cases in the
United States are almost always imported from other countries by travelers or
immigrants. It has been estimated that there are 2 million new cases of
leishmaniasis every year in the world, of which 1.5 million are categorized as
cutaneous leishmaniasis and 0.5 million are visceral leishmaniasis. Epidemics
occur when people are displaced into affected regions through war or migration
or when people in affected regions experience high rates of disease or
malnutrition.
Figure 1: Picture of a sand fly biting a human arm. SOURCE: CDC/Frank Collins
The word "rash" means an outbreak of red bumps on the body. The way people use this term, "a rash" can refer to many different skin conditions. The most common of these are scaly patches of skin and red, itchy bumps or patches all over the place.
Anemia is the condition of having less than the normal number of red blood cells or less than the normal quantity of hemoglobin in the blood. The oxygen-carrying capacity of the blood is, therefore, decreased.
There are many symptoms involved in the 1st, 2nd and 3rd trimesters of pregnancy. The first early pregnancy symptom is typically a missed period, but others include breast swelling and tenderness, nausea and sometimes vomiting, fatigue and bloating. Second trimester symptoms include backache, weight gain, itching, and possible stretch marks. Third trimester symptoms are additional weight gain, heartburn, hemorrhoids, swelling of the ankles, fingers, and face, breast tenderness, and trouble sleeping. Read more to learn about recommended procedures and tests for each stage of a healthy pregnancy.
HIV (human immunodeficiency virus) is the cause of AIDS (acquired immunodeficiency syndrome). HIV is a type of virus called a retrovirus, which infects humans when it comes in contact with a break in the skin or tissues such as those that line the vagina, anal area, mouth, or eyes.
Lymph nodes help the body's immune system fight infections. Causes of swollen lymph nodes (glands) may include infection (viral, bacterial, fungal, parasites). Symptoms of swollen lymph nodes vary greatly. They can sometimes be tender, painful or disfiguring. The treatment of swollen lymph nodes depends upon the cause.
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.
Drug addiction is a chronic disease that causes drug-seeking behavior and drug use despite negative consequences to the user and those around him. Though the initial decision to use drugs is voluntary, changes in the brain caused by repeated drug abuse can affect a person's self-control and ability to make the right decisions and increase the urge to take drugs. Drug abuse and addiction are preventable.
Scar formation is a natural part of the healing process after injury. The depth and size of the wound incision and the location of the injury impact the scar's characteristics, but your age, heredity and even sex or ethnicity will affect how your skin reacts.
Lymph nodes are an important component of the body's immune system and help
in fighting infections.
They are small, soft, round or oval structures that are found throughout the
body and are connected to each other in chain-like (lymphatic chains) fashion by
channels similar to blood vessels. Each individual lymph node is covered
by a capsule made up of connective tissue.
Within the capsule, lymph nodes contain certain kinds of
immune cells. These
cells are mainly lymphocytes, which produce proteins that capture and fight
viruses and other microbes, and macrophages, which destroy and remove the
captured material.
Where are the lymph nodes located in the body?
Lymph nodes are located throughout the body. Some are directly under the skin
while others are deep inside the body. Even the most superficial (close to the
skin) lymph nodes are usually not visible or palpable (felt by touchi...