Microsporidia MB is found predominantly associated with Anopheles gambiae s.s and Anopheles coluzzii in Ghana

Abstract

A vertically transmitted microsporidian, Microsporidia MB, with the ability to disrupt Plasmodium development was reported in Anopheles arabiensis from Kenya, East Africa. To demonstrate its range of incidence, archived DNA samples from 7575 Anopheles mosquitoes collected from Ghana were screened. MB prevalence was observed at 1.8%. An. gambiae s.s constituted 87% of positive mosquitoes while the remaining were from An. coluzzii. Both sibling species had similar positivity rates (24% and 19%; p = 0.42) despite the significantly higher number of An. gambiae s.s analysed (An. gambiae s.s = 487; An. coluzzii = 94; p = 0.0005). The microsporidian was also more prevalent in emerged adults from field-collected larvae than field-caught adults (p < 0.0001) suggestive of an efficient vertical transmission and/or horizontal transfer among larvae. This is the first report of Microsporidia MB in Anopheles mosquitoes in West Africa. It indicates possible widespread among malaria vector species and warrants investigations into the symbiont’s diversity across sub-Saharan Africa.

Microsporidia MB in the primary malaria vector Anopheles gambiae s.s. is avirulent and undergoes maternal and horizontal transmission

“…gambiae s.s. and An. colluzii (~1.8%)from Ghana [11]. Overall, these observations indicate that Microsporidia MB does naturally infect An.…”

“…Microsporidia MB is present in Anopheles species outside of An. arabiensis [11], however the characteristics of these infections and levels of similarity with Microsporidia MB in An. arabiensis have not been investigated.…”

“…gambiae, and An. coluzzii populations [9][10][11]. Although Microsporidia MB has been reported in diverse Anopheles species, the infection characteristics in these other species have not yet been investigated.…”

A mathematical model for mapping the insecticide resistance trend in the Anopheles gambiae mosquito population under climate variability in Africa

“…Various strategies have been proposed to circumvent the propagation of insecticide resistance among mosquito vector populations such as the use of bio-pesticides (fungal pathogens) 21 and biological control agents ( Microsporidia MB ) 22 . However, they are associated with certain limitations such as contamination of the environment and low efficacy in the control of vectors 21 , 22 .…”

“…Various strategies have been proposed to circumvent the propagation of insecticide resistance among mosquito vector populations such as the use of bio-pesticides (fungal pathogens) 21 and biological control agents ( Microsporidia MB ) 22 . However, they are associated with certain limitations such as contamination of the environment and low efficacy in the control of vectors 21 , 22 . While the WHO has developed a manual with guidelines for insecticide resistance management at the operational vector control level 23 , the adoption of these strategies at the country level is affected by the limited arsenal of available alternative chemistries needed for mosaics, rotations or mixtures.…”