The skinny on leishmaniasis

University of York scientists have shown skin, not just blood, is a major route by which Leishmania parasites spread from visceral leishmaniasis (VL) patients to the sand fly vector and back to a new host. The findings add a new dimension to epidemiological models for the disease, and give drug developers another angle to consider when testing therapies to prevent or treat it.

Leishmania parasites require mammalian hosts and a sand fly vector that transmits the infection between hosts. Because sand flies are known to feed off pooled blood in the host’s skin, blood parasite count is considered the main predictor of a host’s propensity to transmit the infection, and epidemiological models are based on that assumption. But the sometimes abundant presence of the parasite in the skin raises the unanswered question of whether blood counts alone can accurately predict the risk dissemination...