Leishmaniasis is a parasitic disease found in parts of southern Europe, the tropics, and the subtropics. Classified as a neglected tropical disease (NTD), leishmaniasis is an infection spread by phlebotomine sand flies.
Read on to learn more about how to recognize, treat, and prevent leishmaniasis.
What Is Leishmaniasis?
Leishmaniasis is caused by Leishmania parasites that are transmitted by the bite of phlebotomine sand flies. While this NTD is mostly found in parts of the subtropics and tropics as well as southern Europe, it has been documented in other regions of the world, too.
In the Western Hemisphere, the disease is usually found in Central America, Mexico, and South America, but not Uruguay or Chile. In the Eastern Hemisphere, it’s found in the Middle East, Africa, and parts of Asia, but not in the Pacific Islands or Australia.
There are several types of leishmaniasis:
- Cutaneous, which causes skin sores
- Mucocutaneous, which develops when cutaneous leishmaniasis spreads to the mucous lining inside your mouth or nose
- Visceral, which affects internal organs such as your bone marrow, liver, and spleen
How Does Infection Happen?
Female phlebotomine sand flies can spread Leishmania parasites when they drink the blood of an infected animal, such as dogs and rodents. Once you're bitten by an infected sand fly, you will notice a red ring on your skin. These bites are not always painful, so it’s not always obvious that you’ve been infected.
Additionally, you can get visceral leishmaniasis through blood transfusion or needle sharing. It can also spread from an infected pregnant mother to her baby.
How many people develop this condition every year? It’s estimated that around 700,000 to 1.2 million people develop cutaneous leishmanias every year, while less than 100,000 people develop visceral leishmaniasis.
Who's at most risk? People of all genders and ages are at risk if they go to areas where leishmaniasis occurs. This infection is typically more common in rural areas, so be sure to take precautions as needed if you spend a lot of time outdoors in areas where leishmaniasis occurs.
People at a higher risk for infection include:
- Ornithologists (people who study birds)
- Travelers
- Peace Corps volunteers
- Missionaries
- People who are outside at sunrise, sunset, or night
- Ecotourists
- Soldiers
Reinfection. You can catch cutaneous leishmaniasis even if you’ve had it before. You always need to be careful when you're going to an area with leishmaniasis.
Symptoms
Symptoms depend on whether you have cutaneous, mucocutaneous, or visceral leishmaniasis.
Cutaneous leishmaniasis. Some people with this condition don’t have any symptoms. If you do, however, you may have sores on your skin that can change in appearance and size over time.
These sores can begin as bumps (papules) or lumps (nodules) and may eventually turn into ulcers covered by crust or scab. These sores are typically painless but can also be painful, accompanied by swollen glands.
Cutaneous leishmaniasis typically appears a few weeks or months after you’re initially bitten by an infected sand fly. In some cases, it might take years to occur.
It may also take months or years to heal from the sores, which can leave scars.
Mucocutaneous leishmaniasis. This type of leishmaniasis typically develops years after your cutaneous leishmaniasis sores have healed.
It can cause the following symptoms:
- Stuffy nose
- Mouth or nose sores
- Frequent nose bleeds
If you don’t get treated for this condition, your face may become severely disfigured.
Visceral leishmaniasis. As with cutaneous leishmaniasis, some people with visceral leishmaniasis won’t have symptoms. If you have symptoms, they typically include:
- Weight loss
- Fever
- Swelling of the liver and spleen
- Abnormal blood tests
- Low blood counts, such as a low white blood cell count (leukopenia), low red blood cell count (anemia), and low platelet count (thrombocytopenia)
If untreated, visceral leishmaniasis can be fatal.
Diagnosis
To find out if you have leishmaniasis, you should ask yourself if you’ve been in a part of the world where leishmaniasis occurs and check if you have any of the symptoms covered above.
If you suspect you have leishmaniasis, contact your doctor immediately. If you are in the United States, you should contact the Centers for Disease Control and Prevention (CDC), which can help test you for leishmaniasis.
When testing for leishmaniasis, specimens may be taken from your skin sores or bone marrow to be examined for Leishmania parasites. Blood and DNA tests may also be used.
Treatment
Treatment depends on the type of leishmaniasis you have.
Cutaneous leishmaniasis. Cutaneous leishmaniasis will sometimes go away on its own, but you should get it treated since it can turn into mucocutaneous leishmaniasis.
There are many ways to treat cutaneous leishmaniasis, including low-dose regimens of pentamidine isethionate. You can also get topical treatment such as cauterization, cryotherapy, and the local application of heat. Leishmania is sensitive to heat, so applying heat to your sores can be an effective way of treating this infection.
Mucocutaneous leishmaniasis. Fluconazole is an effective way to treat mucocutaneous leishmaniasis, but it comes with some serious side effects. Other drugs, such as the antifungal agents itraconazole and ketoconazole, can also treat this condition.
Visceral leishmaniasis. Liposomal amphotericin B is the go-to treatment for visceral leishmaniasis, approved by the U.S. Food and Drug Administration (FDA). The FDA has also approved miltefosine to treat visceral leishmaniasis for adults and teens who are not breastfeeding or pregnant.
Paromomycin, an antibiotic, can also be used to treat visceral leishmaniasis.
Prevention
Unfortunately, there currently aren’t any drugs or vaccines to prevent infection. This means that you must take special precautions when traveling to a part of the world where leishmaniasis is found.
To avoid sand fly bites, you should consider the following precautions:
- Avoid outdoor activity during sunrise or sunset
- Sleep in an air-conditioned room with window screens
- Sleep under a bed net that’s been treated with insecticides
- Avoid camping near animal habitats, since some carry leishmaniasis
- Avoid traveling to areas where leishmaniasis can occur
You should also spray sleeping and living areas with insecticides to kill any sand flies present.
