Post-kala-azar dermal leishmaniasis: does it play a role in the transmission of Leishmania donovani in the Sudan?

In 1997 a sudden outbreak of visceral leishmaniasis (VL) occurred in eastern Sudan, coinciding with an increase of post-kala-azar dermal leishmaniasis (PKDL) cases which may in part be because of sylvatic and anthroponotic transmission. Paradoxically, the more VL patients are treated, the higher the frequency of PKDL. If PKDL plays a role in transmission, its treatment would be expected to reduce infection in the area. Treatment of PKDL, however, requires four times the amount of Pentostam used for treating VL, and the drug is both expensive and in short supply.