Vector competence of Aedes albopictus (Skuse) and Aedes aegypti (Linnaeus) for Plasmodium gallinaceum infection and transmission

摘要

Avian malaria caused by Plasmodium gallinaceum is an important mosquito-borne disease. Eradication of this disease remains problematic since its competent vectors are diverse and widely distributed across the globe. Several mosquito species were implicated as competent vectors for this parasite. However, studies on vector competence for P. gallinaceum remain limited. In this study, vector competence in the two most predominant mosquito vectors in tropical countries, Aedes albopictus and Ae. aegypti, was compared. In order to determine their infection rates, Ae. albopictus (> F10), Ae. aegypti (> F10), and Ae. aegypti (F10) mosquitoes were equally divided and allowed to feed on infected chickens with 15 different gametocyte levels (0.1-5.2%). On day five post blood feeding (PBF), 60 mosquitoes from each group were dissected, and the number of oocysts in midgut was examined. Infections with P. gallinaceum were observed in all groups, but the number of oocysts produced was significantly different. To evaluate the transmission ability of these mosquitoes after having been fed on different levels of gametocytes, the infected mosquitoes were allowed to feed on naive chickens on day 10 PBF, and the chicken bloods were monitored for 21 days PBF. All groups of mosquitoes demonstrated a high degree of infection rates. The infection rates in chickens were 80-100% after having been bitten by infected Ae. albopictus ( > F10) and Ae. aegypti ( > F10) and 40-60% by infected Ae. aegypti (F10). These findings demonstrated that Ae. albopictus (> F10) and Ae. aegypti (> F10) were highly competent vectors for P. gallinaceum infections. These mosquitoes play a crucial role in the transmission cycle of this parasite in nature.