Amsterdam - The tropical disease kala-azar, most commonly found in southern Asia and Africa, kills thousands of people every year. The disease, which is also known as visceral leishmaniasis, is caused by a single-cell parasite that is transmitted to humans through the bite of sand flies. Once in the body, the parasite destroys the immune system, leading to death within several months. Whole villages have been wiped out because of kala-azar epidemics.

Scientific research conducted by Médecins Sans Frontières (MSF) has led to great improvements in the diagnosis and treatment of kala-azar.

"It is a neglected disease," says MSF's medical advisor Koert Ritmeijer. "Nowadays we can save almost every patient that we treat from a certain death."

For years, he carried out research on the disease under difficult conditions in war-torn areas of Sudan. On October 11, he will receive his PhD after defending his thesis on efforts to combat kala-azar.

For his research, Ritmeijer tested a new rapid diagnostic tool: a dipstick that reacts with antibodies against the kala-azar parasite found in a drop of a patient's blood. The reaction causes a marker strip to become visible to the eye.

The test has been found to give a correct, positive outcome in 90 percent of infected patients. The dipstick is specially designed for use in areas lacking laboratories or hospitals.

Kala-azar can be treated through a series of daily injections containing antimonials. This drug however, can have severe and ocassionally fatal side effects. MSF has played a leading role in pushing for the introduction of a safer oral medicine, called miltefosine. In a field study done with 580 Ethiopian kala-azar patients, Ritmeijer showed that miltefosine was just as effective as the traditional drug.

MSF has treated more than 75,000 kala-azar patients and cured 90-95 per cent of them. Despite this fact, kala-azar remains a serious health threat. This is due to the growing number of people infected with kala-azar as well as HIV.

"We can temporarily improve their health, but we're lacking effective drugs," says Ritmeijer. "Ultimately, patients who have contracted both diseases will die. HIV and kala-azar are a lethal cocktail."

It could still be decades before a vaccine against kala-azar becomes available.