BRANDON — A former leader of the Vermont Headmasters Association, Richard Hollis Breen, died Tuesday from a five-day illness brought on by eastern equine encephalitis.

The identity of the first Vermonter to die from the disease was released one day before an aerial spraying operation from 8 to 11 p.m. tonight attempts to kill infected mosquitoes in Brandon and Whiting.

A second case of EEE confirmed by the Vermont Health Department is a Sudbury man who remains hospitalized.

Also Wednesday, the Health Department said preliminary lab results indicated a patient from Chittenden County was confirmed to have West Nile virus, also acquired through a mosquito bite.

Breen, 87, was bit by a mosquito and sick for a week before his death, according to the death certificate released by the Health Department.

The rare but deadly virus comes with flulike symptoms but progresses in a short time to affect the brain and spinal cord.

There is no identified treatment or cure.

It is typically spread by a species of mosquito called culiseta melanura, which feeds only on a certain species of songbird, according to Erica Berl, an infectious-disease epidemiologist with the Health Department.

The mosquito bites the bird, then the bird becomes the host. Before the bird becomes immune to EEE, there’s enough time for more mosquitoes to bite the bird and become carriers, Berl said.

Scientists do not know where the virus came from, but Berl said horses were dying from a similar virus in the 1800s and the first humans got sick with EEE in the 1930s in Massachusetts.

Looking at the mosquitoes’ blood meals, 95 percent bite only birds. The rest feed on deer, emus, pheasants, horses, llamas, alpacas and the occasional penguin, seal, cow and human, Berl said.

In the rare human cases, the environment, the number of infected mosquitoes present, and humans’ susceptibility all play a role, Berl said.

The likelihood of a human getting EEE from an infected mosquito depends more on how many mosquitoes there are in an area rather than the health condition of the human, Berl said.

Anyone can get it, and there is no reliable information on why some people get it and some don’t, she said.

She said people and animals who live near the mosquitoes’ breeding ground — cedar swamps — are more at risk.

According to Alan Graham, an entomologist with the state Agency of Agriculture, a larger population of infected mosquitoes exists in Whiting than in other towns.

An average of only six human cases of EEE occur in the U.S. each year, but one out of every three victims dies from it, according to Dr. Harry Chen, the state’s health commissioner.

Breen was the first principal at Otter Valley Union High School in Brandon, serving from 1961 to 1973. He had also led the headmasters organization that is now the Vermont Principals’ Association.

Breen was retired, an avid golfer and lived on his son Peter Breen’s farm, where numerous emus died from the EEE virus last year.

Peter Breen said his father didn’t have any other ailments and was often active outdoors.

“He was a great dad, but more than that he was one of my best friends too,” Breen said Wednesday. “He had been here (on the farm) for the last six years since Mom had died. I got to spend every day with him. I was lucky to have him.”

Peter Breen, co-founder of Naylor & Breen Builders in Brandon, said 19 emus on his Neshobe Farm on Richmond Road died from EEE in late summer 2011.

Breen said the local mosquito control district ground-sprayed the farm after the emus tested positive for EEE and once again this year.

All of his 100 emus have been vaccinated since.

“I have no idea where he was bit,” Breen said Wednesday. “We haven’t seen hardly any mosquitoes this year. Truth of the matter is, I’m sure it was in this area.”

He added, “It’s kind of a shame they don’t have a vaccination for people. It’s been such a rare disease, I’m sure the pharmaceutical companies didn’t find it profitable. I’m sure that if they took the initiative to develop one now, it would be popular with the two cases here in Vermont now.”

A map of tonight’s spray area and more details on prevention and symptoms can be found at healthvermont.gov.

The Health Department declared an imminent health risk for the Brandon area Saturday.

cristina.kumka

@rutlandherald.com