Vector Competence of Laboratory-reared Anopheles stephensi for Plasmodium vivax-infected Blood from Pakistani Patients

Abstract

Malaria is one of the leading causes of death around the world. Plasmodium vivax is supposed to contribute over 80% of total malaria cases in Pakistan. However, data on transmission pattern is inconsistent and scanty in Pakistan. Aim: The present study was aimed to determine the vector competence based on sporozoite rate rather than oocyst rate. Study Design: Laboratory reared female Anopheles stephensi mosquitoes infected with Plasmodium vivax served a study model. Methodology: Anopheles stephensi vectors were reared in the laboratory and fed on Plasmodium vivax infected blood obtained from malaria patients. Progression of parasite was determined by light or fluorescent microscopic examination of midgut or salivary gland of infected mosquitoes. Results: Oocyst and sporozoite rates were found to be 64% and 54%, respectively, which confirmed the vector competence of female mosquitoes. Blood feeding contributed the longer survival of the vector irrespective of the presence or absence of Plasmodium vivax. Conclusions: It is concluded that laboratory reared female Anopheles stephensi mosquitoes support the development of Plasmodium vivax. Blood-fed mosquitoes showed considerable competence for malaria parasite which is dependent on sporozoite rate rather than oocyst rate. The current study exhibited laboratory reared female Anopheles stephensi mosquitoes as a potential source of parasite transmission.