The early buzz
A ‘robust’ mosquito season arrives early
Mosquito season is off to a robust start, experts said, with numbers of the critters unusually high for this time of year. Mosquitoes associated with the dreaded Zika virus have already been spotted in Bridgeport.
The state began trapping on June 4, and testing them for a variety of illnesses, including West Nile virus and Eastern Equine Encephalitis. In that first week, 18,000 mosquitoes comprising 30 species were trapped, said Philip Armstrong, director of
the state’s mosquito management program, run through the Connecticut Agricultural Experiment station.
“We’re definitely above average,” Armstrong said. “It’s been a busy week.”
Last year, during the first week of testing, the state collected just 7,922 mosquitoes. Armstrong said that number was actually much lower than normal, but the average collection for the first week is around 12,000, still marking this year’s number as high.
Armstrong attributed the bumper crop to recent rainfalls and standing water collected in trash cans and other areas, which promotes mosquito breeding. Despite the high numbers, Armstrong said viruses likely won’t be popping up in the trapped mosquitoes for a few weeks.
The two main mosquitoborne illnesses circulating in Connecticut are West Nile virus and Eastern Equine Encephalitis. West Nile, which came to the state in 1999, is more common in humans. Since 2000, there have been 134 cases in Connecticut, including three fatalities.
Most people who are infected with West Nile have no symptoms or may experience mild illness before fully recovering. In some people, particularly the elderly, the virus can cause serious disease that affects the nervous system. Symptoms generally occur three to 14 days following the bite of an infected mosquito, and range from fever, headache, body aches, and nausea to severe headache, high fever, stiff neck, disorientation, muscle weakness, coma, or death.
Eastern Equine Encephalitis is rarer. On average, there are five human cases a year in the United States, and Connecticut didn’t get its first human case until 2013. That year, an adult resident of eastern Connecticut was hospitalized with the illness and eventually died. In 2017, there were no human cases of Eastern Equine Encephalitits and three human cases of West Nile, in Stamford and New Haven.
Mosquitoes are tested for other illnesses, including the Zika virus. Zika can cause, among other things, serious birth defects in babies born to infected mothers. As of October, 2017, 122 people in Connecticut had tested positive for Zika, but none of those cases were acquired locally and, to date, no mosquitoes in the state have tested positive for Zika.
The main mosquito responsible for the spread of Zika, the Aedes aegypti, is rarely found in Connecticut. However, another species responsible for the disease, the Aedes albopictus, or Asian tiger mosquito, is becoming more common here. Armstrong said those mosquitoes were found at two different trapping locations, both in Bridgeport.
The mosquitoes, he said “are more common in urban and suburban settings with more disturbed habitats where there are more containers that collect water.” However, Armstrong said, though it is possible that the Asian tiger mosquitoes could be a vector for Zika in Connecticut, it’s unlikely to happen.
Overall, it’s difficult to predict this early what kind of mosquito season Connecticut will have, Armstrong said.
“I expect the (mosquito) population to build,” he said, but even that could change if the weather shifts dramatically.
Meanwhile, some local health officials said they hadn’t noticed a bump in the mosquito population recently. Trumbull health director Rhonda Capuano said she hadn’t heard many complaints about mosquitoes yet, though the town has already started warning residents to eliminate standing water on their properties and to take other actions to protect themselves from mosquitoes.
Stratford health director Andrea Boissevain echoed those thoughts, and was surprised to hear that the first crop of collected mosquitoes was so large.
“We haven’t gotten a deluge of complaints yet,” she said. “That’s what I’m basing it on.”
West Nile, which came to the state in 1999, is more common in humans. Since 2000, there have been 134 cases in Connecticut, including three fatalities.