An Edgartown bird has tested positive for West Nile virus in the first such case confirmed this year on the Vineyard.
A crow was discovered by a hotel restaurant worker and shipped to the Massachusetts Department of Public Health by Edgartown health agent Matt Poole.
Reached by phone yesterday, Mr. Poole said the worker spotted the crow corpse under a tree near the intersection of Main and Winter streets in downtown Edgartown. Mr. Poole said the discovery is confirmation of what is already assumed: that the virus exists on the Vineyard.
“A dead bird in Edgartown means it’s a Martha’s Vineyard thing,” he said, “but it’s a given that West Nile exists throughout southeastern Massachusetts and at this point it’s sure that it’s in all 50 states.”
The virus mainly affects birds, though humans, dogs, horses and other animals can also be affected. The state health department runs an ongoing publicity campaign from spring through the fall to report dead crows or bluejays, the two species most at risk in Massachusetts.
“They nest high in trees and the mosquitoes bite them in their sleep and it kills them,” said Mr. Poole. “They’re sort of the canaries in the coal mine.”
According to the state health department, 80 per cent of humans infected with the disease never display symptoms. Another 19 per cent experience mild, cold-like symptoms. Around one per cent suffer extreme illness as a result of the virus. The elderly and those with existing health conditions are most at risk.
According to the centers for disease control 3,623 cases were reported last year in the United States, resulting in 124 deaths.
For protection, Mr. Poole recommends quality insect repellent and long-sleeved clothing. He said reducing standing pools of water where mosquitoes breed can also help.
“It’s basically an awareness thing,” he said, adding: “If you like to go down at dusk to the bottom of the garden where there’s lots of mosquitoes, that might not be the smartest thing.”
At the government level the virus is monitored by surveillance, catching mosquitoes, and cataloguing of data.
Dukes County rodent control officer T.G. Hegarty began trapping mosquitoes this year, sending those he captures to the state department for analysis.
Only fresh water mosquitoes carry the virus, making Mr. Hegarty’s job more difficult.
“He’s not happy with the numbers he’s caught. It’s a learned art,” said Mr. Poole.
Some Massachusetts counties have responded by spraying to reduce mosquito numbers and canceling evening outdoor events such as football practice. Mr. Poole feels such measures will not be required on the Vineyard.
“I have two kids playing high school sports, and I don’t think there’s a mosquito problem there. That’s my anecdotal experience,” he said.