Potential of Anopheles philippinensis-nivipes complex mosquitoes as malaria vector in north-east India.

Anopheles philippinensis-nivipes complex mosquitoes, captured in outdoor human landing catches and light traps in human dwellings from four different sites in Assam state and adjoining areas, were examined (n=1670) for the presence of circumsporozoite antigen (CSA) through enzyme linked immunosorbent assays (ELISA), using species specific capture monoclonal antibodies, of Plasmodium falciparum and two Plasmodium vivax polymorphs (Pv 210 and VK 247). In ELISA, 28 pools were found positive for CSA that accounted for minimum sporozoite rate of 1.7% (95% CI 1.11-2.41). Twenty five percent (7/28) of the positive pools were reactive for P. falciparum and between the two polymorphs of P. vivax, VK 247 was predominant with 77% (20/26) of all P. vivax positive pools. Results were suggestive of most likely involvement of Anopheles philippinensis-nivipes complex mosquitoes in malaria transmission in north-east India.