State finds no disease, but lots of mosquitoes

The state of Connecticut is continuing to test mosquitoes for a variety of illnesses, including West Nile.

The state of Connecticut is continuing to test mosquitoes for a variety of illnesses, including West Nile.

Contributed Photo / Contributed Photo

The good news is that the state’s latest mosquito trapping and testing report showed none of the blood-suckers were positive for West Nile or any other mosquito-borne diseases. The bad news is that there were a whole lot more mosquitoes than there were the week before.

In its most recent report, the Connecticut Agricultural Experiment Station showed the, during the week of June 23, 21,999 mosquitoes were tested for a variety of illnesses. That’s a considerable jump from the previous week’s report, which showed that 16,485 mosquitoes were tested.

However, a spike like that isn’t unusual for late June, said Dr. Philip Armstrong, research scientist and director of the mosquito surveillance program at the Connecticut Agricultural Experiment Station.

“Basically, what we see is the number of mosquitoes hits a peak in late June or early July, then starts to taper off,” he said. “So this isn’t anything out of the ordinary.”

One aspect of this year’s trapping and testing that is surprising is that, so far, the number of culex pipiens, one of the main species of mosquitoes that carry West Nile, have been relatively low. But, Armstrong said, “that could change.”

In the most recent report from the Connecticut Agricultural Experiment Station, no mosquitoes tested positive for any mosquito-borne illnesses, including not just West Nile, but also Eastern Equine Encephalitis and Jamestown Canyon Virus. Jamestown Canyon Virus is an emerging infectious disease that was discovered in Colorado in 1961 and is the only disease that has been found so far in mosquitoes this season.

Since trapping and testing began in June, a total of eight mosquitoes have tested positive for Jamestown Canyon virus, in towns as widespread as Westport, West Haven and Canaan.

Though not as publicized as West Nile, two human cases of Jamestown Canyon virus have been reported in Connecticut — one last year, and one in 2001. Nationwide, 166 human cases of the illness have been reported between 2000 and 2018.

Like West Nile and other mosquito-borne illness, Jamestown Canyon causes mild, flu-like symptoms in most people, but can cause more serious illnesses, such as meningitis and encephalitis.