<i>Wolbachia pipientis</i> occurs in <i>Aedes aegypti</i> populations in New Mexico and Florida, USA

Abstract

The mosquitoes <i>Aedes aegypti</i> (L.) and <i>Ae</i>.<i> albopictus</i> Skuse are the major vectors of dengue, Zika, yellow fever, and chikungunya viruses worldwide. <i>Wolbachia</i>, an endosymbiotic bacterium present in many insects, is being utilized in novel vector control strategies to manipulate mosquito life history and vector competence to curb virus transmission. Earlier studies have found that <i>Wolbachia</i> is commonly detected in <i>Ae</i>.<i> albopictus</i> but rarely detected in <i>Ae. aegypti</i>. In this study, we used a two-step PCR assay to detect <i>Wolbachia</i> in wild-collected samples of <i>Ae. aegypti</i>. The PCR products were sequenced to validate amplicons and identify <i>Wolbachia</i> strains. A loop-mediated isothermal amplification (LAMP) assay was developed and used for detecting <i>Wolbachia</i> in selected mosquito specimens as well. We found <i>Wolbachia</i> in 85/148 (57.4%) wild <i>Ae. aegypti</i> specimens from various cities in New Mexico, and in 2/46 (4.3%) from St. Augustine, Florida. <i>Wolbachia</i> was not detected in 94 samples of <i>Ae. aegypti</i> from Deer Park, Harris County, Texas. <i>Wolbachia</i> detected in <i>Ae. aegypti</i> from both New Mexico and Florida was the <i>w</i>AlbB strain of <i>Wolbachia pipientis</i>. A <i>Wolbachia</i>-positive colony of <i>Ae. aegypti</i> was established from pupae collected in Las Cruces, New Mexico, in 2018. The infected females of this strain transmitted <i>Wolbachia</i> to their progeny when crossed with males of Rockefeller strain of <i>Ae. aegypti</i>, which does not carry <i>Wolbachia</i>. In contrast, none of the progeny of Las Cruces males mated to Rockefeller females were infected with <i>Wolbachia</i>.