It’s been super hot and super humid and the mosquitoes that carry the West Nile virus are loving it!
According to Philip Armstrong, Director of the Mosquito Monitoring Program at the Connecticut Agriculture Experiment Station, in New Haven, this highly humid weather accelerates the reproduction of mosquitoes and extends their lifespans, (which is usually no more than a week or two) allowing the insect to pick up West Nile virus from a bird (the carriers of the disease), give the virus time to replicate in the mosquito and then be transmitted by the insect to humans.
“The actual numbers of mosquitoes we have this year in the state are about the same we have had in the past, at this time of year, however, the number of mosquitoes which have tested positive for carrying the West Nile virus are higher, percentage-wise, than normal,” said Armstrong. “We have found double the number of virus-infected mosquitoes this year versus the same time last year.
West Nile Virus first showed up in the state in 1999. Between 2000 and 2017, there have been three fatalities from the virus in Connecticut. However, most West Nile infections are not fatal.
According to Armstrong, Connecticut has over 50 different species of mosquitoes. The Northern House Mosquito or Genus Celux is the one that carries West Nile. These blood-feeding insects are most often found in residential areas and their larvae thrive in catch basins, and anywhere around houses where stagnant water is collected such as plugged up gutters, bird baths, kiddy pools, and even deep puddles.
Armstrong and Roger Wolfe, the Mosquito Management Coordinator for the Department of Energy and Environmental Protection, both suggest that people check their property’s for stagnant water areas and make sure to empty them at least once a week. This will interrupt the bug’s life cycle and help with keeping numbers at bay. They also recommend that people check their window and door screens regularly to ensure that there are no holes or tears and that they are in working order.
The Northern House Mosquito is nocturnal and is most prevalent at dusk and dawn, so it’s best if you can avoid being outside during those times explained Wolfe.
“If you have to be out, make sure to take precautions such as light-colored, loose-fitting clothing, long sleeves and pants if you can, and bug repellent. If you don’t want to spray bug spray directly on your skin, spray it on your clothes instead,” he warned.
The Connecticut Agricultural Extension Station maintains a network of 91 mosquito-trapping stations in 72 municipalities throughout the state. It tests for West Nile virus as well as Eastern Equine Encephalitis (EEE). So far, to date, mosquitoes infected with the West Nile virus have been identified in 28 Connecticut towns with a concentration in lower Fairfield County and New Haven County. There have been 103 positive mosquito samples identified. All positive findings are reported to local health departments and on the extension station website. According to Wolfe, this summer there have been no EEE positive tests, however, that disease is usually seen later in the season.
Although there is concern about the high percentage of mosquitoes currently testing positive for West Nile, the good news, Armstrong said, is that there have been no reported cases in people or animals yet this summer.
(Horses can get West Nile and it can be deadly for them. According to Wolfe there is an equine vaccine for West Nile and he encourages horse owners to vaccinate their animals against the disease).
For more information go to: www.ct.gov/caes.