Skip to Main content Skip to Navigation
Journal articles

Fluctuations at a low mean temperature accelerate dengue virus transmission by Aedes aegypti

Abstract : BACKGROUND: Environmental factors such as temperature can alter mosquito vector competence for arboviruses. Results from recent studies indicate that daily fluctuations around an intermediate mean temperature (26°C) reduce vector competence of Aedes aeygpti for dengue viruses (DENV). Theoretical predictions suggest that the mean temperature in combination with the magnitude of the diurnal temperature range (DTR) mediate the direction of these effects. METHODOLOGY/PRINCIPAL FINDINGS: We tested the effect of temperature fluctuations on Ae. aegypti vector competence for DENV serotype-1 at high and low mean temperatures, and confirmed this theoretical prediction. A small DTR had no effect on vector competence around a high (30°C) mean, but a large DTR at low temperature (20°C) increased the proportion of infected mosquitoes with a disseminated infection by 60% at 21 and 28 days post-exposure compared to a constant 20°C. This effect resulted from a marked shortening of DENV extrinsic incubation period (EIP) in its mosquito vector; i.e., a decrease from 29.6 to 18.9 days under the fluctuating vs. constant temperature treatment. CONCLUSIONS: Our results indicate that Ae. aegypti exposed to large fluctuations at low temperatures have a significantly shorter virus EIP than under constant temperature conditions at the same mean, leading to a considerably greater potential for DENV transmission. These results emphasize the value of accounting for daily temperature variation in an effort to more accurately understand and predict the risk of mosquito-borne pathogen transmission, provide a mechanism for sustained DENV transmission in endemic areas during cooler times of the year, and indicate that DENV transmission could be more efficient in temperate regions than previously anticipated.
Complete list of metadatas

Cited literature [41 references]  Display  Hide  Download

https://hal-pasteur.archives-ouvertes.fr/pasteur-02011018
Contributor : Fanny Sebire <>
Submitted on : Thursday, February 7, 2019 - 3:57:07 PM
Last modification on : Wednesday, May 6, 2020 - 4:10:24 PM
Long-term archiving on: : Wednesday, May 8, 2019 - 3:02:51 PM

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Collections

Citation

Lauren B. Carrington, M. Veronica Armijos, Louis Lambrechts, Thomas W. Scott. Fluctuations at a low mean temperature accelerate dengue virus transmission by Aedes aegypti. PLoS Neglected Tropical Diseases, Public Library of Science, 2013, 7 (4), pp.e2190. ⟨10.1371/journal.pntd.0002190⟩. ⟨pasteur-02011018⟩

Share

Metrics

Record views

132

Files downloads

370