title: Heat Sensitivity of wMel Wolbachia during Aedes aegypti Development.
abstract: The wMel strain of Wolbachia bacteria is known to prevent dengue and Zika virus transmission in the mosquito vector Aedes aegypti. Accordingly, the release of wMel-infected A. aegypti in endemic regions has been recommended by the World Health Organization as a potential strategy for controlling dengue and Zika outbreaks. However, the utility of this approach could be limited if high temperatures in the aquatic habitats where A. aegypti develop are detrimental to Wolbachia. We exposed wMel-infected A. aegypti eggs and larvae to fluctuating daily temperatures of 30-40°C for three, five, or seven days during their development. We found that Wolbachia levels in females emerging from heat treatments were significantly lower than in the controls that had developed at 20-30°C. Notably, seven days of high temperatures starting at the egg stage reduced Wolbachia levels in emerging females to less than 0.1% of the wMel control levels. However, after adult females returned to 20-30°C for 4-7 days, they experienced differing degrees of Wolbachia recovery. Our findings suggest that the spread of Wolbachia in wild A. aegypti populations and any consequent protection from dengue and Zika viruses might be limited in ecosystems that experience periods of extreme heat, but Wolbachia levels recover partially after temperatures return to normal.
authors.affiliation: QIMR Berghofer Medical Research Institute, Royal Brisbane Hospital, Brisbane, Australia.|Leonard and Jayne Abess Center for Ecosystem Science and Policy, University of Miami, Coral Gables, Florida, United States of America.
authors.forename: Jill N
authors.identifier: 0000-0001-7704-072X
authors.initials: JN
authors.lastname: Ulrich
authors.affiliation: Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, Florida, United States of America.
authors.forename: John C
authors.initials: JC
authors.lastname: Beier
authors.affiliation: QIMR Berghofer Medical Research Institute, Royal Brisbane Hospital, Brisbane, Australia.
authors.forename: Gregor J
authors.initials: GJ
authors.lastname: Devine
authors.affiliation: QIMR Berghofer Medical Research Institute, Royal Brisbane Hospital, Brisbane, Australia.
authors.forename: Leon E
authors.initials: LE
authors.lastname: Hugo
mesh_terms: D000330:Aedes / Q000254:growth & development* / Q000382:microbiology*; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D006358:Hot Temperature; D006801:Humans; D007303:Insect Vectors / Q000254:growth & development* / Q000382:microbiology*; D007814:Larva / Q000254:growth & development / Q000382:microbiology; D008297:Male; D020577:Wolbachia / Q000235:genetics / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins