The Hebrew University of Jerusalem Kuvin Center for the Study of Infectious and Tropical Diseases has received a $5 million grant from the Bill & Melinda Gates Foundation for research into visceral leishmaniasis in Ethiopia.

The project will be led by Prof. Alon Warburg, a vector biologist working at the Institute of Medical Research Israel-Canada at the Hebrew University’s Faculty of Medicine.

The project, entitled ‘Studies on the ecology and transmission dynamics of visceral leishmaniasis in Ethiopia’, will comprise thorough investigations to determine the drivers of transmission of Kala-Azar in endemic foci. The ecology of the sand fly vectors and their larval breeding habitats will be characterized and putative reservoir hosts will be incriminated. In parallel, genotypes and drug sensitivities of the Leishmania parasites will be studied in depth. The data gathered will be rigorously analyzed and utilized to identify the weak links in the transmission cycle in order to devise methods for control of the disease.

According to Prof. Warburg, “Visceral leishmaniasis is transmitted by small, mosquito-like insects known as sand flies. Sand flies become infected with Leishmania while sucking blood from an infected person or animal and transmit the disease during subsequent blood meals. Sand fly control is problematic because the breeding sites of their immature stages are unknown, making larval source reduction all but impossible.”

An estimated 500,000 cases of visceral leishmaniasis - also known as Kala-azar - occur annually. More than 90 percent of the cases are concentrated in the Indian sub-continent, East Africa and Brazil. The worst affected region in Africa is southern Sudan and northwest Ethiopia. Kala Azar is considered an emerging disease in Ethiopia where it is frequently associated with HIV/AIDS, a leading cause of adult illness and death. Leishmania donovani parasites multiply inside cells of the immune system producing symptoms that include an enlarged spleen and fevers. If treated with a 30-day course of intra-muscular injections, the cure rate is 95 percent. However, if left untreated, Kala-azar kills 95 percent of its victims.

Co-infection with HIV makes treatment much more complex. Because the immune system is suppressed in HIV-positive patients, Kala-azar relapses are common and patients have to be treated multiple times. Given the difficulties of treating large populations in remote areas and the bleak prospects for co-infected patients, efforts must be made to protect people living in HIV/AIDS-endemic areas from contracting Kala-azar.

This is a collaborative project with Prof. Asrat Hailu from the Faculty of Medicine and Prof. Teshome Gebre-Michael of the Aklilu Lemma Institute of Pathobiology in Addis Ababa University. Additional collaborating institutions include the Hebrew University’s Robert H. Smith Faculty of Agriculture, Food and Environment, Charles University in Prague, the Volcani Center and the Gertner Institute for Trauma and Emergency Medicine Research.

Source: Jerry Barach

The Hebrew University of Jerusalem