Penn Ag Secretary Issues Timely Advice for West Nile Areas

HARRISBURG, Pa., (PR Newswire)  — Pennsylvania Agriculture Secretary George Greig today urged Pennsylvania horse owners to consult their veterinarians about options for West Nile Virus prevention before mosquito season begins.

“From recreational trail riders and trained competitors to top-notch breeding and racing, Pennsylvania’s equine industry represents an important segment of our state’s leading economic driver – agriculture,” said Greig. “Animal health is a top industry priority, and I encourage horse owners to speak to their veterinarians about protecting their animals against encephalitic diseases like West Nile Virus.”

Equine encephalitic diseases are transmitted by mosquitoes and cause inflammation of the brain.

Mosquitoes become more active with warm weather in early spring.

Vaccines are available to help prevent West Nile Virus and other equine encephalitic diseases such as Eastern Equine Encephalomyelitis. Vaccines are usually administered in February or March prior to mosquito season. Horse owners should talk with their veterinarians to determine the best time to start the vaccination process.

Horses vaccinated against Eastern, Western and Venezuelan equine encephalitis are not protected against West Nile Virus.

Greig cautioned that vaccination of horses is not a guarantee of protection against infection. The best way to prevent infection of West Nile Virus is to reduce the risk of exposure to mosquitoes by eliminating mosquito breeding sites. Important steps to be taken include:

  • Dispose of tin cans, plastic containers, buckets, ceramic pots or other unwanted water-holding containers on the property.
  • Pay special attention to discarded tires, which are mosquito breeding sites.
  • Drill holes in the bottom of recycling containers left outdoors. Containers with drainage holes located only on the sides collect enough water to act as mosquito breeding sites.
  • Clean clogged roof gutters every year. Millions of mosquitoes can breed in roof gutters each season.
  • Turn over plastic wading pools and wheelbarrows when not in use.
  • Empty and refill outdoor water troughs, buckets and birdbaths every few days so water does not stagnate.

  • Aerate ornamental pools or stock them with fish. Water gardens can become major mosquito producers if they are allowed to stagnate.
  • Clean and chlorinate swimming pools when not in use. Mosquitoes may breed in the water that collects on pool covers.
  • Use landscaping to eliminate standing water that collects on your property, especially near manure storage areas. Mosquitoes may breed in any puddle that lasts for more than four days.

Additional steps can be taken by horse owners to protect their horses:

  • Reduce the number of birds in and around the stable area. Eliminate roosting areas in the rafters of the stable. Certain species of wild birds are the main reservoir for the virus.
  • Check the property for dead birds, especially crows. Any suspicious birds should be reported online to or by calling the Department of Environmental Protection at 717-346-8238. Use gloves to handle dead birds and place the birds in plastic bags. If not submitting the bird for testing, the bagged bird can be placed in the trash. Wash hands thoroughly with soap and water after discarding the dead bird.
  • Topical preparations containing mosquito repellents are available for horses.

    Read the product label before using.

For more information contact the Pennsylvania Department of Agriculture’s Bureau of Animal Health at 717-783-6897 or visit