Study Examines Bacteria Living in and on Mosquitoes
Published:09 Jan.2023    Source:North Carolina State University
Avoiding mosquitoes to protect against bites is always a good idea. But a new North Carolina State University study shows that the bacteria-ridden exteriors of mosquitoes may be another reason to arm yourself with a swatter.
 
The first-of-its-kind study, published in PLOS ONE, examined both the exterior surface and interior microbiome of mosquitoes found in homes in Africa's Cote d'Ivoire -- the Ivory Coast.
 
"When you're exposed to mosquitoes, you worry about blood feeding," said R. Michael Roe, William Neal Reynolds Distinguished Professor of Entomology at NC State and co-corresponding author of the study. "Our hypothesis is that mosquitoes can physically transfer bacteria by landing on you or by defecating on household surfaces, like flies do.
 
"They may not, but no one has studied it before."
 
Research collaborators at the Centre Suisse de Recherches Scientifiques collected 79 adult female Anopheles coluzzii mosquitoes from homes in a rice-producing province in Cote d'Ivoire. The mosquitoes were sent to NC State for analysis of the microbiome inside and on external body surfaces.
 
Some of the findings were surprising.
 
"We found greater bacterial diversity internally than externally, which didn't match what has been found with blow flies, for example," said Loganathan Ponnusamy, an NC State principal research scholar in entomology and co-corresponding author of the paper.
 
"At the same time, we found lots of external bacterial differences between homes, but not much difference internally between homes, which makes sense. Much of what is found internally relates to nectar or honey consumed as mosquitoes forage outdoors."
 

The researchers also found -- for the first time in the academic literature -- fructobacillus, which is generally found in nectar sources like flowers and beehives, pointing to mosquitoes visiting those plants or nectar sources, said Kaiying Chen, an NC State postdoctoral researcher and first author of the paper.