Effects of an obligate intracellular microsporidian parasite on the microbiota of Aedes aegypti

The microsporidian Edhazardia aedis is an obligate intracellular microsporidian parasite of the yellow fever mosquito Aedes aegypti. E. aedis has a highly complex life cycle which involves both vertical and horizontal transmission in its mosquito host. E. aedis is highly specific to Ae. aegypti and cannot complete its lifecycle in any other organism. Compared to healthy mosquitoes, mosquitoes infected with E. aedis experience severe fitness defects via reductions in longevity, body size, bloodfeeding success, fecundity, and viability of offspring. Furthermore, our research group recently showed that infection with E. aedis significantly compromises the mosquito host’s ability to defend against infection with the opportunistic bacterium Serratia marcescens. Herein, we present novel work which builds off these findings by investigating the effect of E. aedis infection on the bacterial microbiota of adult female mosquitoes. We used a paired (healthy vs E. aedis-infected) mesocosm experimental design with three biological replicates. Larvae were reared in water inoculated with microbes from a natural larval habitat prior to horizontal infection with E. aedis. After infection with E. aedis, larvae were reared to adulthood and the microbiota of n = 8 adult females from each treatment was subjected to high throughput sequencing of the 16S rRNA gene on an Illumina NextSeq 2000 platform. In this work, we will uncover direct or indirect interactions between E. aedis and Ae. aegypti-associated bacteria which may be exploited for future vector control.