Impact of Mycolactone Produced by Mycobacterium ulcerans on Life-History Traits of Aedes aegypti aegypti (L.) (Diptera: Culicidae) and Resulting Habitat Selection for Oviposition

Abstract

Buruli ulcer (BU) is a globally recognized neglected tropical disease caused by Mycobacterium ulcerans. BU is the third most recurrent mycobacterial disease of humans globally after tuberculosis and leprosy. The disease results in dermal tissue necrosis exposing the tissues under the skin. Ulcers can reach 5 to 15 cm in diameter in some patients especially if they do not seek early treatment. Most cases involve individuals between the ages of 4 to 15 years. This disease was first noted in the late 1880’s in Africa and has since been reported worldwide. The exact mode of transmission in BU is unclear; however, it is hypothesized contact with slow-moving rivers and associated biting aquatic insects, such as mosquitoes results in pathogen transmission. Recent research from our group demonstrated mycolactone as an attractant for adult mosquitoes seeking a blood-meal as well as oviposition sites. In this study, the impact of mycolactone (0.05 µg/mL), (0.5 µg/mL), (1.0 µg/mL) on immature life-history of Ae. aegypti (commonly occurs in same environment as M. ulcerans) was examined. We determined percent egg hatch was not significantly different across treatments. However, concentration did impact survivorship of larval mosquitoes to the adult stage. Future research will determine if development in the presence of mycolactone impacts decision-making by resulting mosquitoes seeking oviposition sites. If true, a synergistic effect with regards to the prevalence of BU and other Ae. aegypti associated diseases (e.g., Yellow Fever) may occur.