Infection rate and vectorial capacity of malaria vectors in Jeypore hill tract

The role of different anophelines in malaria transmission in two geoclimatic zones, viz., Jeypore and Malkangiri plateau of Koraput distt., which are endemic for malaria, was studied. Out of 10,110 specimens belonging to 9 species collected and dissected over a period of 12 months by different methods in nine study villages, natural infection (sporozoites and oocysts) was detected in An. fluviatilis in both the zones. The sporozoite and oocyst rates were 0.28% and 1.41% in Jeypore zone and 5.09% and 0.85% in Malkangiri zone, respectively. Sporozoites were also found in a single specimen of An. culicifacies in Malkangiri area. An. annularis was incriminated in an earlier study. The vectorial capacities of An. fluviatilis, An. culicifacies and An. annularis were estimated for the three plasmodial species, viz., P. falciparum, P. vivax and P. malariae in different seasons. The definitive role played by each species in transmission is discussed.