A possible role for Phlebotomus (Anaphlebotomus) rodhaini (Parrot, 1930) in transmission of Leishmania donovani

Abstract

BackgroundVisceral leishmaniasis (VL, kala azar), caused by Leishmania donovani is a major health problem in Sudan and other East African countries. In this region the only proven vectors of L. donovani are Phlebotomus orientalis in eastern Sudan, Ethiopia and Upper Nile areas of Southern Sudan and Phlebotomus martini in Ethiopia, Kenya and Southern Sudan. In this report, we present the first evidence that Phlebotomus rodhaini may also play a role in maintaining transmission of L. donovani between animal reservoir hosts in eastern Sudan. The study was conducted in a zoonotic focus of visceral leishmaniasis in Dinder National Park, eastern Sudan, where previous work showed high infection rates of L. donovani in P. orientalis. Sand flies, captured by CDC traps were dissected and examined for infection with Leishmania parasites. Parasite isolates were subjected to L. donovani specific PCR. Field experiments were also carried out to compare efficiency of rodent baited and un-baited CDC traps in collection of P. rodhaini and determine its man-biting rate.ResultsThree female P. rodhaini were found infected with Leishmania parasites in an astonishingly small number of flies captured in three separate field trips. Two of these isolates were typed by molecular methods as L. donovani, while the third isolate was inoculated into a hamster that was subsequently lost. Although P. rodhaini is generally considered a rare species, results obtained in this study indicate that it can readily be captured by rodent-baited traps. Results of human landing collection showed that it rarely bites humans in the area.ConclusionIt is concluded that P. rodhaini is a possible vector of L. donovani between animal reservoir hosts but is not responsible for infecting humans. It is suggested that the role of P. rodhaini in transmission of L. donovani in other zoonotic foci of visceral leishmaniasis in Africa should be re-examined.

Transmission of Leishmania infantum in the Canine Leishmaniasis Focus of Mont-Rolland, Senegal: Ecological, Parasitological and Molecular Evidence for a Possible Role of Sergentomyia Sand Flies

“…rhodlaini , a previous study showed that this species is probably underestimated because of unsuitable traps and could play a role in L . donovani transmission between animal reservoir hosts [24]. Rodent or dog-baited traps were not used in this study but light traps were placed above and in rodent burrows, around dogs in farming and peridomestic areas and we collected all residual fauna (all the insects staying inside after night) indoor.…”

Visceral Leishmaniasis in Benishangul-Gumuz Regional State, Western Ethiopia: Reemerging or Emerging?

“…This finding suggests that P. rodhaini might be the vector responsible in maintaining a zoonotic cycle in this area uninhabited by humans. 22 The spread of kala-azar is a significant public health concern in Ethiopia and the east African countries in general.…”

Did disease constrain the spread of domestic dogs (Canis familiaris) into Sub-Saharan Africa?

“…A third taxon, P. rodhaini, is a possible vector between animal reservoir hosts, although it is apparently not involved in infecting people (Elnaiem et al 2011). Like L. chagasi/ infantum, this is transmitted by biting sandflies, in this case two species of the genus Phlebotomus: P. orientalis and P. martini.…”