1Leishmaniasis kills 62,000 people every year worldwide. It is however a “neglected” disease which is not within donors’ priorities. This considerably complicates research conducted on this scourge transmitted by sand flies, midges that bite humans as well as animals, particularly dogs, one of their favourite hosts. Scientists realised this when health authorities launched a campaign in Brazil to eradicate dogs infected with leishmaniasis, thereby creating a spike in human contamination as, in the absence of dogs, sand flies settle on humans instead.

Leishmania stained DNA.

••• Researchers are developing a dog vaccine against leishmaniasis •••

2This unexpected result opened a new avenue for researchers. While no one was willing to fund research on human leishmaniasis, the same could not be said for canine leishmaniasis, which threatens 25 million dogs in southern Europe. In 1990, this reality enabled researchers to raise money and finally study the leishmaniasis parasite in dogs. It took five years for them to develop a serum-free culture medium, i.e. without animal contaminant, and allow the pathogen to multiply.

Dog suffering from leishmaniasis, Senegal.

3They subsequently studied how the parasite infects cells in the canine immune system and discovered a promising approach with a view to a vaccine. This vaccine does not trigger the production of antibodies but of immune cells capable of eliminating infected cells. In the parasite secretions, they isolated proteins capable of triggering this immune response. After 12 years of research and clinical tests, in 2011 they managed to bring a dog vaccine against leishmaniasis to market. At the same time, they worked together to develop a human vaccine, attempting to reduce production costs to make it available to the populations concerned. An initial human vaccine should enter into phase 1 clinical trials shortly.

“The existence of the disease must be acknowledged and integrated into the strategic plans of the ministries of health.” 
Bashir Mwambi, International University of Health Sciences, Kampala, Uganda