EEE, WEE AND WNV
ADDITIONAL PREVENTIVE MEASURES:
• Limit mosquito populations. Mosquitoes lay their eggs in calm, stagnant water, so take steps to close the breeding grounds. That means picking up old tires and other debris that can catch rainwater, overturning unused wheelbarrows, and keeping drainage ditches and rain gutters flowing freely. Also repair dripping faucets, and clean water troughs and buckets regularly.
• Maintain healthy ponds and streams. Fish and other predators will feed on mosquitoes and their larvae and help to keep their numbers down. Your local extension agent can advise you on how to properly manage natural water sources on your property.
• Use fly sprays. Check that your fly sprays are also effective against mosquitoes, and apply them to your horses prior to turnout and before riding on trails that go near wetlands.
• Bring horses inside at dawn and dusk, the hours when mosquitoes are most active. Mosquitoes are weak fliers and avoid breezes, so a few well-placed fans will also deter them from approaching your horses.
� The vaccine: A single bivalent vaccine protects against both EEE and WEE (and provides some immunity against VEE as well). The vaccine is an inactivated adjuvanted whole virus product--that is, it contains both whole viruses, which have been rendered inactive by mixing them with a formaldehyde solution called formalin, combined with an adjuvant---a substance that stimulates a greater immune response to encourage the production of more antibodies against the viruses.
The first time a mature horse is vaccinated, or for a horse whose history is unknown, the recommended schedule is two doses of vaccine spaced four to six weeks apart. Thereafter, mature horses can be vaccinated once per year, prior to the start of mosquito season. In areas where the mosquitoes remain active yearround, your veterinarian may recommend booster vaccines every six months, especially for horses with compromised immunity.
The AAEP also suggests that pregnant mares receive a booster four to six weeks before they are scheduled to deliver, and that foals of vaccinated mares receive a three-dose series at four- to sixweek intervals, beginning at 4 to 6 months of age. Your veterinarian will be able to make more specific recommendations based on your local climate and conditions and your horse’s own health needs and risks.
EASTERN EQUINE ENCEPHALOMYELITIS