Small RNA sequencing of field Culex mosquitoes identifies patterns of viral abundances and the mosquito immune response.

In this study, we sequenced small RNA samples from over 2,000 Culex mosquitoes, in 63 pools, from two major areas of Southern California from 2017 to 2019 to elucidate the virome and immune responses of Culex. Our results demonstrated that small RNAs not only allowed the detection of viruses but also revealed distinct patterns of viral infection based on location, Culex species, and time. We also identified factors likely involved in Culex immune responses to viruses and Wolbachia bacteria, and show the utility of using small RNA to detect antiviral immune pathways.