Study finds abundant disease-transmitting mosquito species in deforested areas

Most disease-transmitting mosquito species live in deforested areas, a finding that may influence decisions on where and when to cut down trees, a new University of Florida study shows.

Deforestation occurs when people remove trees to make way for neighborhoods, farms, shopping centers and other land uses, said Nathan Burkett-Cadena, a UF/IFAS entomologist and lead author of the study.

For their study, Burkett-Cadena and Amy Vittor, a UF assistant professor of infectious diseases and global medicine, synthesized and examined data from prior studies that had looked at how many pathogen-carrying mosquito species made their homes in forested lands vs. non-forested lands in 12 countries worldwide, including the United States.

They found that about half -- 52.9 percent -- of the species were more abundant in deforested habitats. Of those species that favored deforested areas, more than half --56.5 percent – carry viruses harmful to humans, the study showed. More importantly, all of the species that carry multiple human pathogens were more common in deforested land, said Burkett-Cadena, a faculty member at the UF/IFAS Florida Medical Entomology Laboratory in Vero Beach, Florida.

"This research shows that when we convert forest to other uses, we make habitat for the mosquitoes that carry our diseases," said Burkett-Cadena. "The takeaway message is that our forests provide benefits above and beyond the biodiversity they sustain, the products they provide -- such as food, lumber and medicine -- and the recreational opportunities that they provide. Forests are poor habitat for most of our disease-carrying mosquitoes."

"Humans need to take this into account as we make decisions and policies about what we do with our remaining forests," Burkett-Cadena said. "Given the rapid pace of global land-use change and deforestation, it is imperative that these dynamics are better understood to mitigate disease risk and guide land-use policy."

Mosquito-borne diseases account for more than 17 percent of infectious diseases in people, according to the World Health Organization. The most common virus, dengue, is estimated to infect 390 million people per year, according to a 2013 study led by an Oxford University researcher.