The Register Citizen (Torrington, CT)
Invasive mosquito surviving winter
NEW HAVEN >> The Asian tiger mosquito, which thrives in urban and suburban environments and readily feeds on humans, can survive the winter in Connecticut and could help spread West Nile virus, according to an article published by the Connecticut Agricultural Experiment Station.
The mosquito, Aedes albopictus, was first discovered in Connecticut in 2006, then not again until 2010, with rising numbers since then. But what the agency confirmed is that eggs laid in the fall will hatch the next spring, according to Philip Armstrong, director of the mosquito-monitoring program at the ag station.
When it comes to West Nile virus, “This could change the risk for sure, in that this mosquito, the Asian tiger mosquito, is found in urban locations and feeds readily on humans,” Armstrong said Tuesday. West Nile is spread by mosquitos feeding on infected birds and then biting people, he said.
“We don’t know whether Aedes albopictus is significantly going to change the risk of West Nile virus at this point, but it’s worth monitoring,” Armstrong said Tuesday.
Researchers took tires from Bridgeport in which Asian tiger larvae had been found, stored them over the winter, then flooded them this spring, Armstrong said. “We were able to recover hatching mosquito eggs. We showed that this mosquito could overwinter here in Connecticut,” he said.
The Asian tiger mosquito is an invasive species that originated in East Asia. In warmer parts of the United States it can spread diseases such as chikungunya, dengue and Zika. But it isn’t bringing those diseases to Connecticut, Armstrong said.
“It’s a new species of mosquito that’s entering the picture here in Connecticut, but it’s not bringing new viruses with it,” he said.
West Nile, though, is present in Connecticut, with 122 insects, mostly Culex pipiens mosquitoes, found to be carrying the disease in 2016, according to the agency, which collected about 174,000 mosquitoes statewide.
Armstrong said there was just one human case of West Nile reported to the state Department of Public Health in 2016. The statewide average is eight, he said.
Like other species, the Asian tiger mosquito breeds in standing water, which is most usually found in urban and suburban environments, Armstrong said. “You don’t find it in the woods so much,” he said.
“We would anticipate further expansion and build-up of this species with projected climate change,” said Theodore Andreadis, co-author of the study and director of the Agricultural Experiment Station in a release. “Its aggressive biting behavior and ability to transmit a cadre of human disease causing viruses clearly warrant further study and close monitoring through our statewide surveillance program.”
Most people who contract West Nile virus do not develop symptoms, according to the Centers for Disease Control and Prevention. About 20 percent will show symptoms such as fever, headache, body ache, joint pain, diarrhea or rash, according to the CDC.
The research, part of a state-supported mosquitoborne disease surveillance program, was conducted from 1997 to 2016. The article was published in the journal PLoS Neglected Tropical Diseases.