West Nile virus is back in Solano County, health officials reported Tuesday.
A dead crow found in Dixon has tested positive for the virus, according to a message on the county's Web site.
"This is the first confirmed bird West Nile virus case of 2012 in Solano County, and the first confirmed indication of local WNV activity for this year," said Dr. Bela Matyas, the county's public health officer.
WNV can be transmitted to humans and animals from mosquitoes who feed on the blood of infected birds.
The virus can cause severe discomfort in humans but is generally not fatal; horses, however, are especially susceptible.
Those possibilities are have prompted county officials to warn Solano residents to take steps to avoid exposure to mosquitos and horse owners to be sure their animals are vaccinated.
"It is important for residents to avoid exposure to mosquitoes, and for horse owners to vaccinate their horses," Mayas said.
Horses should be vaccinated against West Nile virus at least annually and horse owners should consult with their veterinarians about the need for vaccinations in their specific area, he said.
Most horses infected with West Nile virus eventually recover, but the disease is believed to have caused fatalities in some animals.
While the county regularly monitors the mosquito population to protect against West Nile, all residents can join the battle, said Jon Blegen, manager of the county's Mosquito Abatement District,
"Unmaintained swimming pools due to home foreclosures have become a problem statewide and can potentially produce the types of mosquitoes that spread (the virus)," Blegen said.
"If you have seen a green pool, please report it to us at 437-1116."