MISSISSIPPI STATE -- Dead birds in Mississippi are attracting attention as careful observers look for the first indication West Nile virus has again appeared in their county.

Dead birds that test positive for the virus indicate West Nile has arrived in an area. Humans and horses can get the virus after being bitten by disease-carrying mosquitoes. The best prevention for humans is good insect repellent and up-to-date vaccinations for horses.

Sharon Sims, health programs specialist senior with the Mississippi State Department of Health, said the department is asking the public to watch for all dead birds.

"We take reports on any dead birds, and we test house sparrows, blue jays, cardinals and crows," Sims said. "These are the more prominent birds that die of the virus."

As of mid-May, Mississippi had just one confirmed case of West Nile virus, that of a dead crow found in Covington County. Last year, the first human case appeared in early June.

Anyone who finds a dead bird of one of these four species should take it to the local health department. Take precautions when handling a dead bird. Wear gloves or cover hands with plastic bags and double-bag the bird. Keep it refrigerated or on ice until submitted to the health department. Dead birds of other species should be reported to the state health department. The MSDH offers a West Nile virus hotline at (877) WST-NILE or (877) 978-6453.

Sims said senior citizens and those with compromised immune systems are most at risk from this virus. Normally healthy people are at little risk, as most people who contract the virus recover. As with any virus, if diagnosed, only the symptoms can be treated.

"Most who get sick don't even know they're sick," Sims said. "Some get a headache or flu-like symptoms for two or three days. Others develop encephalitis or meningitis. A physician will decide if the West Nile virus test needs to be run."

The best way to prevent the disease is to stay away from mosquitoes. Sims recommended cleaning up mosquito-friendly areas around homes, eliminating breeding opportunities offered by standing water and wearing mosquito repellant. Those containing DEET, listed on the label as NN-diethyl-m-toluamide, work best. Sprays containing permethrin can be used on clothing, tents or sleeping bags.

Dr. Stanley Robertson, Mississippi State University Extension Service veterinarian, said horses are susceptible to West Nile virus and other diseases such as Eastern and Western encephalomyelitis, tetanus and influenza. Many horses in Mississippi should be vaccinated against these diseases two to four times a year.

"Vaccinations almost always prevent diseases, and it's better for the horses' health to vaccinate them instead of taking the chance of them getting a disease that could cause serious illness or even death," Robertson said.

"Whether or not a horse needs these vaccinations depends on its environment and region," he said. "The decision to vaccinate against these diseases should be made in consultation with a licensed veterinarian."

Horses should visit a veterinarian at least annually to receive vaccinations and be checked for internal parasites. Follow-up vaccinations should be given either by a veterinarian or at that person's recommendation.

Some of what prevents humans from being bitten by mosquitoes works for horses, too.

Eliminate nearby standing water and remove weeds and brush because these can harbor mosquitoes. Keep horses indoors during the peak mosquito feeding times of dawn and dusk, and turn barn lights off or use fluorescent lights to minimize the number of mosquitos attracted inside. Use fans to keep air moving inside barns, and apply insect repellants that contain permethrin to horses.