Horse on West Slope infected with West Nile Virus

A horse living in the Greenwood community of El Dorado County has been infected with West Nile Virus according to county health officials.

"The horse is recovering and expected to survive, but the case reminds us that the virus is circulating and horse owners need to take precautions," said Fred Sanford with the El Dorado County Environmental Management Division (EMD). "Horses exposed to West Nile Virus (WNV) are vulnerable to serious complications and even death. Fortunately, a vaccine is available from many veterinarians that can protect horses."

Horses can get WNV when they are bitten by a mosquito that has the virus. Signs of the disease in horses include fever, stumbling, staggering, wobbling, weakness, muscle twitches or inability to stand. A veterinarian should be consulted if a horse is exhibiting these signs. Not every horse exposed to the virus gets WNV. Of those horses that exhibit WNV symptoms, approximately 30 percent die from the illness. Horses cannot give WNV to people or other animals.

Vaccination for WNV is recommended as a core standard of care for all horses in North America. Vaccination generally protects the horse for one year. There is no WNV vaccine for humans or other domestic animals; however, llamas and alpacas may benefit from the horse vaccine.

Horse owners should consult with their veterinarian to ensure current WNV vaccination status in their horses and to discuss the use of safe, effective mosquito repellents. DEET-containing products are NOT approved for pets and may cause poisoning.

Currently, there are no known human cases of WNV in El Dorado County for 2015; four birds have tested positive for the virus in the County this year. Residents are urged to help reduce the spread of WNV in the community by draining standing water around property and keeping water in swimming pools, ponds and troughs circulating or treated for mosquitoes.

The El Dorado County EMD conducts mosquito surveillance and control programs. For more information, or to set up an inspection and treatment for standing water sources, contact EMD at (530) 621-5300.