Additional evidence on the efficacy of different Akirin vaccines assessed on Anopheles arabiensis (Diptera: Culicidae)

Abstract

[Background]: Anopheles arabiensis is an opportunistic malaria vector that rests and feeds outdoors, circumventing current indoor vector control methods. Furthermore, this vector will readily feed on both animals and humans. Targeting this vector while feeding on animals can provide an additional intervention for the current vector control activities. Previous results have displayed the efficacy of using Subolesin/Akirin ortholog vaccines for the control of multiple ectoparasite infestations. This made Akirin a potential antigen for vaccine development against An. arabiensis.

[Methods]: The efficacy of three antigens, namely recombinant Akirin from An. arabiensis, recombinant Akirin from Aedes albopictus, and recombinant Q38 (Akirin/Subolesin chimera) were evaluated as novel interventions for An. arabiensis vector control. Immunisation trials were conducted based on the concept that mosquitoes feeding on vaccinated balb/c mice would ingest antibodies specific to the target antigen. The antibodies would interact with the target antigen in the arthropod vector, subsequently disrupting its function.

[Results]: All three antigens successfully reduced An. arabiensis survival and reproductive capacities, with a vaccine efficacy of 68–73%.

[Conclusions]: These results were the first to show that hosts vaccinated with recombinant Akirin vaccines could develop a protective response against this outdoor malaria transmission vector, thus providing a step towards the development of a novel intervention for An. arabiensis vector control.