Light Pollution Drives Increased Risk of West Nile Virus

Typography

Florida has experienced a relatively mild winter, which typically translates to more mosquitoes in the summer and more birds on which they can feast. 

Florida has experienced a relatively mild winter, which typically translates to more mosquitoes in the summer and more birds on which they can feast. If history repeats itself, it’s likely there will be an uptick in West Nile virus cases this year, especially in the outer fringes of the suburbs where much of the nighttime illumination emanates from the skyglow of nearby cities.

A new study from the University of South Florida (USF) is the first to provide direct evidence that light pollution is driving infectious disease patterns in nature. The research team previously determined mosquitoes and birds are attracted to light, greatly enhancing the likelihood that they’ll spread West Nile virus to animals and humans. Their new findings published in the “Proceedings of the Royal Society B” are in contrast to previous studies that have blamed urbanization due to its human population density and breeding hotspots, such as drainage systems.

“We knew that light pollution could affect host immune defenses and behavior,” said lead author Meredith Kernbach, doctoral student in the USF College of Public Health. “But what we didn’t know until now is that light pollution can significantly affect when and where West Nile virus emerges in nature.”

The research team, which includes collaborators from the University of Georgia and California Polytechnic State University, modeled West Nile virus exposure data from the Florida Department of Health. They studied 6,468 antibody samples from sentinel chickens collected between the months of June and December over four years in 105 coop locations throughout the state. Researchers found most cases of West Nile virus were present in chickens exposed to low levels of light compared to those surrounded by unpolluted and intensely light-polluted areas.

Read more at University of South Florida (USF Innovation)

Image: University of South Florida researchers studied 6,468 antibody samples from sentinel chickens collected by the Florida Department of Health. (Credit: Alissa Berro Pinellas County Public Works Department)