Dominance of the tiger: The displacement of Aedes aegypti by Aedes albopictus in parts of the Torres Strait, Australia

Abstract

Most of the inhabited islands in the Torres Strait region of Australia have experienced dengue outbreaks transmitted by <i>Aedes aegypti</i> at various times since at least the 1890s. However, another potential dengue vector, <i>Aedes albopictus</i>, the Asian tiger mosquito, was detected for the first time in 2005 and it expanded across most of the Torres Strait within a few years. In 2016, a survey of container-inhabiting mosquitoes was conducted in all island communities and <i>Ae. aegypti</i> was undetectable on most of the islands which the species had previously occupied, and had been replaced by <i>Ae. albopictus</i>. It is suspected that competitive displacement was responsible for the changes in species distribution. <i>Aedes aegypti</i> was only detected on Boigu Island and Thursday Island. Recent dengue outbreaks in the Torres Strait have apparently been driven by both <i>Ae. albopictus</i> and <i>Ae. aegypti</i>. The findings have major implications on management of dengue outbreaks in the region.