06 Sep 17 08 Jan 20

Kala azar

Kala azar is the second-largest parasitic killer in the world — only malaria is more deadly. Along with Chagas disease and sleeping sickness, kala azar is one of the most dangerous neglected tropical diseases.

MSF has treated over 100,000 people with the disease since 1988.

Kala azar is endemic in 47 countries with approximately 200 million people at risk of infection.

The parasite is spread to humans by bites from infected female sand flies. It attacks the immune system, and is almost always fatal if not treated.

There are around half a million new cases a year, about 90 per cent of which are in India, Bangladesh, Nepal, Sudan and Brazil.

What causes kala azar?

Kala azar is caused by infection with Leishmania parasites, transmitted through the bite of the female phlebotomine sand fly—.

Symptoms of kala azar

Initially, leishmania parasites cause skin sores or ulcers at the site of sand fly bites. If the disease progresses, it attacks the immune system.

Kala azar presents after two to eight months, with more generalized symptoms including prolonged fever and weakness.

Diagnosing kala azar

The most effective diagnostic tests for leishmaniasis are invasive and potentially dangerous, where tissue samples are required from the spleen, lymph nodes or bone marrow. These tests require lab facilities and specialists not readily available in the resource-poor areas where the disease is most prevalent.

The most common method of diagnosing kala azar is by dipstick blood testing. However, this method is problematic. In endemic areas, people can become infected with kala azar but may not develop the disease or require treatment.

Unfortunately, dipstick testing only looks for an immune response to the parasite, not whether the parasite is still present. —Because of this, dipstick testing can’t be used to see if the patient is cured, is re-infected or has relapsed.

Treating kala azar

There are different treatment options available for kala azar, with varying effectiveness and side effects. Pentavalent antimonials are usually the first line drugs, given as a 30-day course of intramuscular injections.

While antimonials are toxic and present a risk to patients, those who are cured of kala azar almost always develop immunity for life. Researchers hope to identify ways to simplify treatment regimes, improve their safety and reduce the risk of drug resistance.

Since 1988 MSF has treated more than 100,000 patients with kala azar. MSF is also campaigning for more research into suitable diagnostic techniques and affordable drugs to treat this neglected disease.

In 2012, MSF treated 5,860 people for kala azar.

Check out the interactive guide to kala azar: