State epidemiologists and other volunteers are out for blood at deer-tagging stations across the state, as part of efforts to track the spread of a primarily mosquito-borne disease deadly to people and horses.

State Epidemiologist Dr. Stephen Sears said so far their findings indicate the disease, Eastern equine encephalitis, or EEE, is more widespread than previously thought.

“We’re finding the virus is far more dispersed in the state than we had any information about,” Sears said Sunday. “We’re concerned it is spreading in the state. We’re working with the federal Centers for Disease Control and partners in the state to find ways to see where it is spreading.”

One of those ways is testing the blood of deer shot by hunters.

Sears said deer do not seem to become ill from being bitten by a mosquito carrying EEE, but they do produce an antibody to fight it off. So researchers track the prevalence of that antibody in deceased deer to help track the spread of EEE.

Which makes hunters partners in the effort, though, for most, they’re unknowing partners until they’re approached by a worker or volunteer at a tagging station and asked to allow a sample of the animal’s blood to be collected.

“It’s entirely voluntary, but we’ve been doing this three years, and nobody has ever said they won’t give us blood,” Sears said. “Hunters have been very supportive. And they’ve been curious about what we’re doing.”

One of the things hunters are most curious about: If their deer is found to have been bitten by an EEE-carrying mosquito, is the venison safe to eat?

Sears explains the virus is not actually in the deer — it’s the antibody deer put out when they are bitten that is still present.

“You can’t get it from a deer,” Sears said of EEE. “It’s absolutely safe to eat.”

In 2009, more than a dozen horses in Maine were killed by EEE, many in Waldo County. Sears said that scare raised awareness of the disease, and prompted more horse owners to have their animals vaccinated against the disease.

The disease also kills some birds.

Maine has had only one documented case of a person having EEE, a Massachusetts man visiting the Naples area. The elderly man later died at a Massachusetts hospital due to the disease.

Sears said most human cases of EEE in New England have been in Massachusetts.

However, he said, the state’s three years of studying the disease by taking blood samples from deer has shown EEE has spread farther north than previously thought.

“What we can’t fully answer is whether it was already there, and it just hadn’t been documented, or if it is indeed spreading,” said Sears, who spent the previous Saturday taking blood samples from deer at a tagging station in Palmyra.

This past Saturday, samples were collected at Fuller’s Market in West Gardiner.

Sears said they hope to get at least 25 to 30 specimens from each region of Maine.

When they take a sample from an animal, they ask the hunter where he shot it, so they can map it.

Sears said organizers of the primarily federally funded effort also hope to collect blood samples from moose.

Keith Edwards — 621-5647

kedwards@centralmaine.com