Different prevalences of Plasmodium vivax phenotypes VK210 and VK247 associated with the distribution of Anopheles albimanus and Anopheles pseudopunctipennis in Mexico.

The geographic distribution of Plasmodium vivax circumsporozoite protein phenotypes from patient blood used to infect colonized Anopheles albimanus and An. pseudopunctipennis was investigated in southern Mexico. Parasite phenotype types were determined in blood samples by a polymerase chain reaction and oligoprobe hybridization or by immunofluorescent assay of sporozoites. The proportion of infected mosquitoes and the number of oocysts per mosquito confirmed previous in vitro observations indicating that An. albimanus is more susceptible to VK210 and that An. pseudopunctipennis is more susceptible to VK247. All patients living on the coast were infected with VK210 and most patients living above 170 meters above sea level had VK247. Both phenotypes infected patients from intermediate altitudes. These results concur with the distribution of the anophelines, indicating that An. albimanus is the main vector of the phenotype VK210, but that An. pseudopunctipennis transmits both phenotypes. These conditions have direct implications on parasite transmission rates and malaria epidemiology in Mexico.