Leishmaniasis

What is leishmaniasis?

Leishmaniasis is a disease that is spread by female phlebotomine sand flies. It is caused by a number of different species of the Leishmania parasite.

There are three types of leishmaniasis: cutaneous leishmaniasis, mucocutaneous leishmaniasis (also called mucosal leishmaniasis) and visceral leishmaniasis (also called kala-azar). Cutaneous leishmaniasis, which affects the skin, is the most common type of leishmaniasis. 

There is no vaccine or medication to protect against leishmaniasis.

What is my risk?

• The risk for most travellers is low.
• If travelling in areas where leishmaniasis occurs, the risk is higher for those who are:
  • travelling in rural, jungle, desert and forested areas.
  • participating in outdoor activities like bird watching or hiking.
  • outside between sundown and sunrise.
  • adventure travellers, ecotourists, military personnel, construction workers and missionaries.
• People who have had leishmaniasis are still at risk of getting it again.

How is it transmitted?

• Female phlebotomine sand flies become infected with Leishmania parasites when they feed on the blood of an infected mammal, like dogs, rodents, or humans.
• The Leishmania parasites are spread to a human when he or she is bitten by the infected sand fly.
• Sand flies are hard to notice because they are very small (smaller than mosquitoes) and do not make noise. Sand fly bites are also hard to notice because they are not always painful, but the bites can be recognized because they usually leave a red ring.
• Visceral leishmaniasis can also be spread through blood transfusion, needle sharing and from an infected pregnant mother to her baby.

What are the symptoms?

Cutaneous leishmaniasis

• Cutaneous leishmaniasis usually appears weeks or months after a bite from an infected sand fly, but might even occur years later.
• Cutaneous leishmaniasis causes sores, like scabs or ulcers, on the skin. Lymph nodes near the sores may be swollen.
• The sores, which can be painful or painless, usually take months or years to heal and usually leave scars.

Mucocutaneous leishmaniasis

• Mucocutaneous leishmaniasis occurs when cutaneous leishmaniasis spreads to the mucous membranes (the lining) inside the nose or mouth.
• Symptoms of mucocutaneous leishmaniasis include the feeling of a “stuffed up” nose, frequent nose bleeds, and mouth or nose sores.
• Mucocutaneous leishmaniasis sores might develop years after the cutaneous leishmaniasis sores have healed.
• Mucocutaneous leishmaniasis can cause severe disfiguration of the face, if it is not treated.

Visceral leishmaniasis

• Visceral leishmaniasis occurs when Leishmania parasites infect the internal organs, like the spleen, liver, and bone marrow.
• Visceral leishmaniasis usually appears weeks or months after a bite from an infected sand fly, but might even occur years later, especially if a person’s immune system is weakened.
• Symptoms of visceral leishmaniasis include fever, weight loss, enlarged liver and spleen, and blood abnormalities (e.g. anemia, low white blood cell count).

• Visceral leishmaniasis can be fatal if it is not treated.

Can leishmaniasis be treated?

• There are treatments available for all three types of leishmaniasis.
• Cutaneous leishmaniasis can sometimes heal on its own.

Where is leishmaniasis a concern?

• Leishmaniasis occurs in tropical and subtropical areas, including parts of:
  • Africa, particularly the tropical region and North and East Africa.
  • The Americas, mainly South and Central America, but occasional cases are reported in the southern United States.
  • Asia (including the Middle East), especially South and Central Asia.
  • Southern Europe and the Mediterranean region.
• Most cutaneous leishmaniasis cases occur in Afghanistan, Algeria, Bolivia, Brazil, Colombia, Iran, Iraq, Nicaragua, Peru, Saudi Arabia, and Syria.
• Most mucocutaneous leishmaniasis cases occur in Bolivia, Brazil, Ethiopia and Peru.
• Most visceral leishmaniasis cases occur in Bangladesh, Brazil, Ethiopia, India, Nepal, South Sudan and Sudan.
• Leishmaniasis is usually more common in rural areas, but can also be found in urban areas.

Recommendations 

Consult a health care provider or visit a travel health clinic preferably six weeks before you travel.

1. Prevent sand fly bites.

• Avoid outdoor activities between sunset and sunrise.
• Sleep in air-conditioned, screened-in rooms or sleep under a bed net treated with pyrethroid insecticides.
  • Ordinary, untreated bed nets are not effective at preventing leishmaniasis because sand flies are small enough to pass through the netting. 
  • Closely-woven bed nets are more effective.
• Sand flies generally fly near the ground so sleeping off the ground can help reduce your risk. If you are camping, avoid placing your tent near animal burrows, as some animals could carry leishmaniasis.

2. If you develop symptoms similar to leishmaniasis when you are travelling or after you return, see a health care provider and tell them where you have been travelling or living.

• Symptoms may develop weeks, months, or even years after you travel to an area where leishmaniasis occurs.