Leishmaniasis is an infection with Leishmania, a group of parasitic protozoa. Leishmania parasites are found in tropical and subtropical areas of the world. It can cause severe ulcers on your skin (cutaneous leishmaniasis) or infection of your internal organs that can be fatal (visceral leishmaniasis). Anti-parasitic medications treat leishmaniasis.
Leishmaniasis (pronounced “leesh-muh-NAI-uh-suhs”) is a group of illnesses caused by many types of Leishmania parasites. You get it from sand fly bites. It can cause disfiguring skin ulcers and life-threatening illnesses.
Leishmania parasites are protozoa, one-celled organisms that are too small to see without a microscope. The two most common kinds are cutaneous leishmaniasis and visceral leishmaniasis.
Leishmaniasis most often affects people living in rural areas of tropical regions or areas with inadequate sanitation. People with HIV and other conditions that weaken their immune system are more likely to get sick from a Leishmania infection.
Since many people can get infected with Leishmania without developing symptoms, it can be hard to know how common leishmaniasis is. Experts estimate that there are 1.5 million to 2 million people worldwide who develop symptoms per year.
Leishmania exists in over 90 countries around the world. Different types of Leishmania are found in different parts of the world. Experts use the terms “Old World leishmaniasis” and “New World leishmaniasis” depending on where it’s found.
Old World leishmaniasis is found in the Eastern Hemisphere, including:
New World leishmaniasis is found in the Western Hemisphere, including:
While it’s uncommon in the U.S., people have gotten cutaneous leishmaniasis in Texas and Oklahoma.
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Leishmaniasis falls into three main categories: cutaneous, mucosal (or mucocutaneous) and visceral.
Cutaneous leishmaniasis (CL) is an infection in your skin where a sand fly bit you. It causes bumps (nodules) that turn into large ulcers over time. It can take a long time to heal on its own. Symptoms start a few weeks or months after a sand fly bite.
Very rarely, you can have bumps or ulcers on many areas of your skin (diffuse cutaneous leishmaniasis). These can come back again and again (recur), even with treatment.
Mucosal, or mucocutaneous leishmaniasis (ML), is usually a complication of cutaneous leishmaniasis. Ulcers develop in your nose, mouth or throat (mucous membranes). ML rarely gets better on its own and is usually fatal if left untreated. It can cause facial disfigurement.
Visceral leishmaniasis (VL), also called kala-azar, is a serious form of the disease caused by specific types of Leishmania. It affects your internal organs, like your spleen and liver. Symptoms sometimes take a few months or a year or more to develop after an infected fly bites you. VL can cause severe disease quickly. It’s fatal if left untreated.
Symptoms of leishmaniasis depend on what type you have. Cutaneous and mucosal leishmaniasis cause large, slow-healing ulcers. Visceral leishmaniasis causes general symptoms, like fever, weight loss and abdominal swelling.
Cutaneous leishmaniasis causes a bump on your skin where a sand fly bit you. It can have scabs or a crust. Over time, it changes to an ulcer, with a hard border and a sunken center (like a volcano).
Mucosal leishmaniasis causes ulcers or sores in your nose, mouth or throat (mucous membranes). You usually have one or more ulcers on your skin that appear at the same time or before those in your mucous membranes.
Visceral leishmaniasis symptoms include:
Leishmania parasites cause leishmaniasis. They live in humans and animals, including dogs, cats, possums, rodents and foxes.
Leishmaniasis spreads through the bite of the phlebotomine sand fly. The sand fly bites an infected person or animal, then bites someone else, injecting them with the parasite Leishmania. Less common ways Leishmania can infect you include:
No, you can’t get leishmaniasis directly from a dog or any other animal. But there’s evidence that dogs can infect other dogs. Since it can spread from dogs to people through sand fly bites, it’s still important to prevent dogs from getting infected.
A provider diagnoses leishmaniasis by looking at tissue samples from your body for Leishmania. These samples could include tissue from ulcers, your spleen, a lymph node or your bone marrow. In countries where leishmaniasis is common, providers often diagnose it based on hearing your symptoms or looking at your skin.
Tests your provider might perform to diagnose leishmaniasis include:
There a several anti-parasitic medications available that treat leishmaniasis. The specific medication a provider prescribes depends on what type of leishmaniasis you have. Medication can come in different forms, including:
If you have cutaneous leishmaniasis, your provider may be able to apply thermotherapy, cryotherapy or laser therapy directly to your wounds. These can kill the parasite and help your wound heal.
Medications providers use to treat leishmaniasis include:
Providers can sometimes give you other therapies for cutaneous leishmaniasis. They include:
The best way to prevent all forms of leishmaniasis is to avoid sand fly bites, especially in areas where Leishmania is common. Ways to avoid bites include:
The outlook for leishmaniasis depends on which type you have and whether you have a healthy immune system. Visceral and mucosal leishmaniasis need to be treated immediately. If left untreated, both are nearly always fatal.
Cutaneous leishmaniasis can go away on its own or with treatment. It can take months to fully resolve and leave permanent scars on your skin.
You may need to take medication for a long time — several weeks or months — to make sure your infection is completely gone. Ask your provider what to expect in terms of treatment and recovery time.
Leishmaniasis is often curable when a provider diagnoses and treats it with medication right away. The cure rate with prompt treatment is over 90% for visceral leishmaniasis and over 75% for mucosal leishmaniasis. Some people who get better and don’t have signs of parasites after treatment will get sick again within a few months (relapse).
Visceral and mucosal leishmaniasis get harder to cure the longer they’re left untreated. They’re also harder to cure in people with weakened immune systems.
Complications of leishmaniasis can be serious or life-threatening, especially for the visceral and mucosal types. They include:
Additional complications of visceral leishmaniasis include:
Ask your provider about ways to take care of yourself until you recover. If you have cutaneous leishmaniasis, your provider will tell you how to clean and take care of your wounds until they heal. With all forms of leishmaniasis, watch for signs of your symptoms returning, even after you feel better.
See your healthcare provider:
You only need to see a healthcare provider if you have symptoms after a fly bite. Not all sand flies carry diseases. It’s common for people’s bodies to fight off a Leishmania infection without getting sick. Unless you have a weakened immune system, your provider usually doesn’t need to treat you if you don’t get sick.
Go to the nearest emergency room if you have symptoms of serious illness, including:
It might be helpful to ask your healthcare provider:
A note from Cleveland Clinic
Leishmaniasis can cause wounds that don’t heal and life-threatening illness. If you live in or are traveling to an area where Leishmania is common, take precautions to protect yourself. See your provider if you have symptoms of leishmaniasis or a wound that’s not healing or getting worse. Most people who are treated before they get seriously ill can fully recover.
Last reviewed by a Cleveland Clinic medical professional on 12/12/2022.
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