A third person in the state has died from eastern equine encephalitis, and a fourth case has been confirmed, as municipalities weigh additional measures to reduce the risk of the disease.

An East Haddam resident, who is over 60, died the third week of September after becoming ill the week prior, the state Department of Public Health announced Tuesday.

The Centers for Disease Control and Prevention also confirmed that a Colchester resident between ages 40 and 49 is hospitalized with EEE, DPH said. The resident became sick during the third week of August.

DPH is urging residents to minimize outdoor activity from dusk to dawn, when mosquitoes are most active, and avoid "unnecessary trips into marshes and freshwater swamps," which are mosquito breeding grounds.

"Sadly, this has been an unprecedented year for EEE activity in Connecticut," Dr. Matthew Cartter, DPH's state epidemiologist, said in a statement. Prior to this year, Connecticut had only one human case of EEE, in 2013, he said.

Cartter said the four people with EEE "were most likely exposed to infected mosquitoes sometime between August 11, 2019 and September 8, 2019, which was the peak period of mosquito activity in Connecticut."

“All four residents live in a part of eastern Connecticut where EEE activity has not been a problem before this summer,” he said.

“In the southeastern part of the state from the lower Connecticut River valley to the Rhode Island border region, the risk of becoming ill as a result of being bitten by a mosquito infected with EEE virus is low but not zero,” he added. “The forecast is for cooler weather to arrive by the weekend, but the risk of EEE will not be gone until the first hard frost.”

Reducing risks

Ledge Light Health District last week reissued an advisory for residents of Groton, Ledyard, Lyme, North Stonington, Old Lyme and Stonington to avoid outdoor activities between dusk and dawn.

Both the town and city of Groton have canceled activities on their recreational fields after 5:30 p.m. "until a determination is made that such use is safe again." Schools in Old Lyme, Stonington, New London, Norwich and other towns have taken similar precautions, moving up practices and suspending games to avoid risks.

Neighboring states also have seen an uptick in EEE infections this year. Massachusetts has seen three deaths this year. Rhode Island, which has one confirmed death so far, has been conducting aerial spraying of insecticide to target mosquitoes that carry the virus. 

A plane spraying over Westerly also flew over Pawcatuck last week, prompting complaints from residents along with state and town officials. While several legislators have requested such spraying in Connecticut, DPH said Tuesday that there are no plans to do so at this time.

A state Department of Energy and Environmental Protection official told Ledge Light Health District health director Stephen Mansfield that a representative from the company overseeing the nighttime spraying in Westerly said that while the plane did go over part of Connecticut, it uses a program called Flight Master that is very accurate and takes into account variables, such as wind direction, altitude and temperature, to ensure the chemical lands only in the desired location.

"He has every confidence that the product landed on target" in Rhode Island and not Connecticut, DEEP official Roger Wolfe wrote in an email to Mansfield.

Stonington First Selectman Rob Simmons said aerial spraying is not approved in Connecticut. The town does conduct ground spraying of areas where EEE-infected mosquitoes have been trapped, such as behind the high school.

Simmons said that after he received reports of the plane over Pawcatuck, including one in which the resident claimed to be able to smell the chemical, he contacted Mansfield, who in turn contacted DEEP, which then contacted Rhode Island officials. On the Stonington Community Forum Facebook page, a number of residents posted comments about planes overhead at night and worrying about spraying.

An online flight tracker map provided to Simmons by North Stonington First Selectman Mike Urgo shows the plane repeatedly flying in a north-south direction over a large section of Pawcatuck just west of the Pawcatuck River on the night of Sept. 25.

According to the Rhode Island Health Department, the chemical being sprayed is Anvil 10+10, "a product extensively tested and used in both ground-level and aerial spraying in the U.S. to control mosquitoes." It contains two active ingredients: Sumithrin and Piperonyl butoxide.

"Sumithrin has proven to be extremely effective in killing mosquitoes worldwide for over 20 years. The chemical properties for Anvil provide the widest margins of safety for human and environmental health when used properly by certified professionals trained to use mosquito control pesticides," according to Rhode Island's health department.

Meanwhile, resident and attorney Matthew Berger has suggested the Stonington Board of Education consider starting school later until the first hard frost. While the high school has changed practice and game times for sports teams to avoid dusk, he wrote that "each day I see high school students outside waiting for the bus in the morning, exposing themselves to the risk of infection with EEE."

He noted the state health department recommends avoiding being outside at all around dawn. Sunrise is 6:45 a.m. Wednesday and will continue to get later each successive day until Nov. 2, when it will be 7:20 a.m. It then will become an hour earlier with the end of daylight saving time. Berger pointed out that Stonington's first frost typically occurs between Oct. 11 and 20, with the first hard frost following sometime thereafter.

He also wrote that earlier this year he asked the board to consider a later starting date "based on the growing consensus that later start times are beneficial for students." While that remains true and "a public health crisis is not an ideal situation, acting now to protect our students during the EEE outbreak would also provide the Board with an excellent opportunity to study the impact of altering the start time and implementation of changes, should it decide to eventually do so full time," he wrote.

Board Chairwoman Alexa Garvey could not be immediately be reached to comment about Berger's request.

Taking precautions

EEE is among the most severe illnesses transmitted by mosquitoes, DPH said. It is introduced by infected birds that migrate in the spring from Florida, where the virus circulates year-round. Mosquitoes pick up the virus when they feed on infected birds and can transmit it to horses and humans. It cannot be transmitted from horses to humans or from one human to another.

The virus can cause serious illness affecting the brain. It is fatal in 25 percent to 50 percent of cases and many people who survive suffer from lasting health problems. Symptoms include high fever, headache, stiff neck and decreased consciousness, and anyone with these symptoms should contact their physician immediately, DPH said.

"Most persons infected with EEE have no apparent illness, however some can be very ill," DPH said. "Severe cases of EEE (involving encephalitis, an inflammation of the brain) begin with the sudden onset of headache, high fever, chills, and vomiting 4 to 10 days after a mosquito bite. The illness may then progress to disorientation, seizures or coma."

There is no cure for the disease and no specific treatment or vaccine for it.

The Connecticut Agricultural Experiment Station, which traps mosquitoes at 92 sites in 72 municipalities in the state, on Monday added Bethany and Middlefield to the list of places where mosquitoes infected with the virus have been found. Electronic signs have been posted along highways warning drivers to avoid being outdoors from dusk to dawn.

To further reduce risk of infection, residents are urged to ensure door and window screens are tight-fitting and in good repair. While outdoors, wear shoes, socks, long pants and long-sleeved shirts, all made of tightly woven materials. Consider using mosquito repellent — the most effective ones contain DEET or Picaridin, though oil of lemon eucalyptus also is effective for short periods — when outdoors and always use them according to label instructions. If sleeping outdoors, use mosquito netting.

To reduce mosquitoes around the home, dispose of water-holding containers, such as ceramic pots, used tires, and tire swings, and unclog gutters. Drill holes in the bottom of containers such as those used for recycling so water does not collect in them, and change water in bird baths weekly. Clean and chlorinate swimming pools, and cover pools when not in use. Use landscaping to eliminate areas where water can collect.

Additional resources and information on EEE and mosquito management can be found at bit.ly/CTmosquito.

Day Staff Writers Kimberly Drelich, Joe Wojtas, Brian Hallenbeck, Mary Biekert and Jacinta Meyers contributed to this report.