The mosquitoes that bring the dreaded West Nile Virus to Connecticut each summer are back, and they’re early.
Field teams from the Connecticut Agricultural Experiment Station trapped the season’s first virus-positive bug in Milford on June 21.
Philip Armstrong, a virologist and medical entomologist in the Department of Environmental Sciences at the Center for Vector Biology & Zoonotic Diseases in CAES, said his colleagues usually don’t come across WNV-bearing insects until early- to mid-July.
Armstrong said we have no more control over the mosquito infestations and subsequent WNV outbreaks than we do the weather.
West Nile virus has been detected in Connecticut every year since it was introduced into North America in 1999, when it “exceeded all our expectations,” Armstrong said. “It re-emerges every summer, it’s extremely dependable, and the levels of virus activity will fluctuate a lot from year to year, and that’s really just depending on the summer weather.”If it’s a hotter than average summer, the state is in for a heavy toll of WNV cases, Armstrong said. Last season, West Nile Virus was detected in 143 mosquito pools from 21 towns in Fairfield, Hartford and New Haven counties, with eight human cases. In 2019, CAES tracked WNV in 82 mosquito samples from 23 towns, and one human case was reported. The year before, 158 cases of West Nile virus were reported in Connecticut, of which four were fatal.
