What is leishmaniasis?
Leishmaniasis (LEASH-ma-NIGH-a-sis) is a parasitic
disease spread by the bite of infected sand flies. There are several different
forms of leishmaniasis. 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, 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 often end up looking somewhat like
a volcano, with a raised edge and central crater. 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 (usually the spleen is bigger than the liver). Some patients have
swollen glands. Certain blood tests are abnormal. 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?
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?
Leishmaniasis is found in
parts of about 88 countries. Approximately 350 million people live in these
areas. Most of the affected countries are in the tropics and subtropics. The
settings in which leishmaniasis is found range from rain forests in Central and
South America to deserts in West Asia. More than 90% of the world's cases
of visceral leishmaniasis are in India, Bangladesh, Nepal, Sudan, and Brazil.
Leishmaniasis is found in some parts of the following areas:
- in Mexico, Central America, and South America—from northern Argentina to
Texas (not in Uruguay, Chile, or Canada)
- southern Europe (leishmaniasis is not
common in travelers to southern Europe)
- Asia (not Southeast Asia)
- the Middle East
- Africa (particularly East and North Africa, with some cases elsewhere)
Leishmaniasis is not found in Australia or Oceania (that is, islands in the
Pacific, including Melanesia, Micronesia, and Polynesia).