While you’re watching Little League games or walking the dog this spring, don’t forget the mosquito repellent.
Because of the heavy rains in March and the subsequent unusually warm weather, mosquitoes are becoming active earlier than usual this year, according to Chief Medical Entomologist at the Connecticut Agricultural Experiment Station, Theodore Andreadis.
And Andreadis is concerned that the abundance of mosquitoes will increase the chances that one carrying the Eastern Equine Encephalitis virus will bite and infect someone.
He is particularly concerned about New London County, he said, because this is where the most mosquitoes with the EEE virus have been found in the past.
“We had very high numbers last year because of the wet summer,” he said. “Fortunately we had no human cases, but there was one in New York and one in New Hampshire.”
While no Connecticut residents contracted EEE last year, a horse and a pheasant flock in the state were infected.
According to the Centers for Disease Control and Prevention, the illness is characterized by a sudden onset of headache, high fever, chills and vomiting. It may progress into disorientation, seizures or coma.
Although there are relatively few cases in the United States each year, those who do become infected can become seriously ill. About one-third die, and most survivors have significant brain damage. There is no treatment or vaccine.
Andreadis said it is unclear at this point whether to also expect an increase in mosquitoes with West Nile virus, a less serious infection than EEE. In the past, most cases of West Nile have occurred in the western half of the state.
“There’s plenty of larva, and they’re developing very rapidly,” he said, based on recent surveys he and his staff did at swamps and marshes where mosquitoes are known to hatch.
“The aggressive human-biters will be out in early May and June,” he said.
Wetlands are full of developing larva and so full of water that few if any will dry out before the nymphs mature, he said. (When there are typical spring rainfall levels, some wetlands dry out before the mosquitoes have a chance to fully develop.)
“With the very high amount of rainfall, the water table is very high, and the larvae are developing in the white cedar and red maple swamps,” he said. “The numbers will be very high, no question about it.”
He recommends that people consider placing briquettes that release bacillus thuringiensis, a biological treatment, into any wetlands on their property to kill the larvae before they develop into adults.
“I would do it right now,” he said. “It’s very effective.”
Also, he stressed, getting rid of any standing water in birdbaths, old tires, flowerpots and other receptacles is doubly important this year, because larvae will grow there, too.
The mosquitoes some people have been noticing during the recent warm spell are adults that live through the winter and become active again as soon as the temperatures warm, he said.
The agricultural experiment station’s mosquito trapping and testing program is scheduled to begin at its regular June 1 date. Traps are set in 90 locations around the state. Samples from the traps are brought back to the New Haven lab to determine whether any carry EEE or West Nile virus, and if so, public health officials and the public are notified. The program runs through October.
Posted April 10 – as edited by HTNP.com Editor Brenda Sullivan, and reprinted here in cooperation with The Chronicle