Spread of equine disease linked to decline in use of vaccine

By JULIET WANG
Capital News Service
LANSING—A mosquito-borne disease may have spread among horses in Michigan this year due to a decrease in vaccines used, according to a state expert.
Eastern equine encephalitis (EEE) is a virus which can infect horses and humans and is usually carried by birds and mosquitoes.
“I think there was a decline of the use of the vaccine because of the economy. It’s unfortunate because it might mean the loss of a horse,” said Steve Halstead, the state veterinarian in the Department of Agriculture.
The increase of confirmed cases of infected horses this year is not connected to the number of confirmed human cases, Halstead said. There were three confirmed human cases, two in Kalamazoo County and the third in Barry County, according to the Department of Community Health.
Horse cases were reported in 10 counties, including in Allegan, St. Joseph, Cass, Eaton and Oakland.
“Humans cannot not get it from a horse. If a mosquito bites an infected horse then bites a human, the human cannot get it,” said Halstead.   “It cannot travel from horse to horse because the horse doesn’t generate enough of the virus to be transmitted.”
He said vaccination each spring is recommended for horses.
“There are vaccines for humans but it’s not widespread and not readily available to the general public. It has existed for decades,” said Steven Bolin Diagnostic Center for Population and Animal Health at Michigan State University College of Veterinary Medicine.
“Usually the people who get this vaccine are people who work in laboratories and are in frequent contact with this disease,” Bolin said.
James McCurtis, a Community Health communications officer, said the three cases confirmed this year are the only ones reported since 2002.
“It’s a concern but not alarming,” said McCurtis. “We announced it because we want people to be aware of it.”
The human symptoms include chills, headache, nausea and fever.
The symptoms for horses include fever, seizures, loss of appetite and stumbling.  Often the horse is down and unable to get up.
The Agriculture Department has received more than 50 reports of dead horses and 18 horses tested positive for the virus this year.
© 2010, Capital News Service, Michigan State University School of Journalism. Not to be reproduced without permission.