Invasive Aedes japonicus Mosquitoes Dominate the Aedes Fauna Collected with Gravid Traps in Wooster, Northeastern Ohio, USA

SIMPLE SUMMARY: Aedes japonicus is an invasive mosquito in America and it is considered as a secondary vector of arboviruses. Little is known about the distribution and abundance of Ae. japonicus in many states of the United States of America. In this study, CDC light, BG-sentinel, and gravid traps were used to collect mosquitoes between June and October 2021, in Wooster, Northeastern Ohio, USA. Morphological identification unveiled that, Ae. japonicus mosquitoes were the most abundant mosquito species collected with gravid traps in Wooster in 2021, confirming its establishment in Ohio. A phylogenetic analysis of Ae. japonicus revealed 100% nucleotide similarity with those found in Iowa (USA), Canada and Belgium, suggesting multiple introductions. Its presence may increase the risk of future pathogens outbreaks in Wooster, Ohio. Future works should include the genetic diversity characterization of Ae. japonicus in Wooster. ABSTRACT: Aedes japonicus (Diptera: Culicidae), or the Asian rock pool mosquito, is an invasive mosquito in Europe and America. It was first detected outside of Asia in 1990 in Oceania. It has since expanded to North America and Europe in 1998 and 2000, respectively. Even though it is classified as a secondary vector of pathogens, it is competent to several arboviruses and filarial worms, and it is contributing to the transmission of La Crosse virus (LACV) and West Nile virus (WNV). In this study, CDC light, BG-sentinel, and gravid traps were used to collect mosquitoes between June and October 2021, in Wooster, Northeastern Ohio, USA. Morphological identification or/and Sanger sequencing were performed to identify the collected mosquitoes. Our results revealed that (adult) Ae. japonicus mosquitoes were the most abundant mosquito species collected with gravid traps in Wooster in 2021, confirming its establishment in Ohio. Molecular analyses of Ae. japonicus showed 100% nucleotide similarity with Ae. japonicus collected in Iowa (USA) and Canada, suggesting multiple introductions. Its presence may increase the risk of future arbovirus outbreaks in Wooster, Ohio. This study stresses the importance of actively monitoring the density and distribution of all members of the Ae. japonicus complex.