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Alphabetical Listing | Travel
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Alphabetical Listing | Travel |
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 Leishmania Infection(Leishmaniasis)
What is leishmaniasis?Leishmaniasis (LEASH-ma-NIGH-a-sis) is a parasitic disease that is found in parts of the tropics, subtropics, and southern Europe. It is caused by infection with Leishmania parasites, which are spread by the bite of infected sand flies. There are several different forms of leishmaniasis in people. The most common forms are cutaneous (cue-TAY-knee-us) leishmaniasis, which causes skin sores, and visceral (VIS-er-al) leishmaniasis, which affects some of the internal organs of the body (for example, spleen, liver, and bone marrow).
What are the signs and symptoms of cutaneous leishmaniasis?People who have cutaneous leishmaniasis have one or more sores on their skin. The sores can change in size and appearance over time. They may end up looking somewhat like a volcano, with a raised edge and central crater (ulcer). Some sores are covered by a scab. The sores can be painless or painful. Some people have swollen glands near the sores (for example, under the arm if the sores are on the arm or hand).
What are the signs and symptoms of visceral leishmaniasis?People who have visceral leishmaniasis usually have fever, weight loss, and an enlarged spleen and liver (typically, the spleen is bigger than the liver), and some abnormal blood tests. For example, patients usually have low blood counts, including a low red blood cell count (anemia), low white blood cell count, and low platelet count.
How common is leishmaniasis in the world?The number of new cases of cutaneous leishmaniasis each year in the world is thought to be about 1.5 million. The number of new cases of visceral leishmaniasis is thought to be about 500,000.
In what parts of the world is leishmaniasis found?In the New World (the Western Hemisphere), leishmaniasis is found in some parts of Mexico, Central America, and South America (Latin America). It is not found in Chile or Uruguay. In the Old World (the Eastern Hemisphere), leishmaniasis is found in some parts of Asia, the Middle East, Africa, and southern Europe. It is not found in Australia or the Pacific Islands. Overall, leishmaniasis is found in focal areas of about 88 countries. Some of these countries account for most of the world’s cases of leishmaniasis:
However, the cases of leishmaniasis evaluated in the United States reflect travel and immigration patterns. For example, cases in U.S. civilian travelers typically are cases of cutaneous leishmaniasis (rather than of visceral leishmaniasis) acquired in common tourist destinations in Latin America (rather than in places in the Old World).
Is leishmaniasis found in the United States?Almost all of the people in the United States who have leishmaniasis became infected while traveling or living in other countries. Occasional cases of cutaneous leishmaniasis have been reported in residents of Texas and Oklahoma. No cases of visceral leishmaniasis are known to have been acquired in the United States.
How do people get infected with Leishmania parasites?The main way is through the bite of infected female phlebotomine sand flies. (Sand flies become infected by biting an infected animal or person.) People might not realize that sand flies are present because:
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.
Who is at risk for Leishmania infection?People of all ages are at risk for infection if they live or travel where leishmaniasis is found. Leishmaniasis usually is more common in rural than in urban areas; but it is found in the outskirts of some cities. The risk is highest from dusk to dawn because this is when sand flies generally are the most active. Examples of people who may have an increased risk for infection include adventure travelers, ecotourists, Peace Corps volunteers, missionaries, soldiers, ornithologists (people who study birds), and other people who do research (or are active) outdoors at night/twilight.
If I were bitten by an infected sand fly, when would leishmaniasis develop?Some infected people do not have any signs or symptoms. However, the skin sores of cutaneous leishmaniasis usually develop within a few weeks or months of the sand fly bite. People with visceral leishmaniasis usually become sick within months (sometimes as long as years) of when they were bitten.
What should I do if I think I might have leishmaniasis?See your health care provider. Be sure to say where you have traveled and to mention the possibility of leishmaniasis.
How is leishmaniasis diagnosed?The first steps are to check if you have been in a part of the world where leishmaniasis is found and if you have any signs or symptoms that might be from leishmaniasis. Samples of tissue (for example, from skin sores) can be examined for the parasite under a microscope, in cultures, and through other means. Blood tests that detect antibody (an immune response) to the parasite can be helpful for cases of visceral leishmaniasis; tests to look for the parasite itself usually are done also. CDC staff can advise your health care provider and can help with the laboratory testing. Diagnosing leishmaniasis can be difficult. Sometimes the laboratory tests are negative even if a person has leishmaniasis.
Does leishmaniasis have to be treated?Your health care provider can talk with CDC staff about whether your case of leishmaniasis should be treated, and, if so, with what type of therapy. The skin sores of cutaneous leishmaniasis usually will heal on their own, even without treatment. But this can take months or even years, and the sores can leave ugly scars. Another potential concern applies to some (not all) types of the parasite found in South and Central America: occasionally, the parasite spreads from the skin to the nose or mouth and causes sores there (mucosal leishmaniasis). Mucosal leishmaniasis might not be noticed until years after the original skin sores healed. The best way to prevent mucosal leishmaniasis is to treat the cutaneous infection before it spreads. If not treated, severe (advanced) cases of visceral leishmaniasis can cause death.
I plan to travel to an area of the world where leishmaniasis is found. What can I do to prevent infection?No vaccines or drugs to prevent infection are available. The best way for travelers to prevent infection is to protect themselves from sand fly bites. To decrease the risk of being bitten: Avoid outdoor activities, especially from dusk to dawn, when sand flies generally are the most active. When outdoors (or in unprotected quarters):
When indoors:
See CDC's Traveler's Health recommendations on Protection against Mosquitoes, Ticks, Fleas and Other Insects and Arthropods. NOTE: Bed nets, repellents, and insecticides should be purchased before traveling and can be found in hardware, camping, and military surplus stores.
If I have already had leishmaniasis, could I get it again?Yes. Some people have had cutaneous leishmaniasis more than once. Therefore, you should follow the preventive measures listed above whenever you are in an area where leishmaniasis is found.
This fact sheet is for information only and is not meant to be used for self-diagnosis or as a substitute for consultation with a health care provider. If you have any questions about the disease described above or think that you might have a parasitic infection, consult a health care provider.
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Info CDC Home | CDC Search | CDC Health Topics A-Z This page last reviewed September 22, 2008 Centers for Disease Control and Prevention
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