Novartis Animal Vaccines announced Aug. 19 the conditional licensing and availability of the only antibody product approved by the USDA to help control disease caused by West Nile virus (WNV) in equids. This product helps an exposed animal by increasing the antibody level in the circulatory system, which enhances an animal’s ability to neutralize virus already in the blood.

For a product to get USDA conditional approval, the company must show that the product is safe, pure, and that there’s reasonable expectation of efficacy. West Nile Virus Antibody is a prescription antiserum product, administered intravenously by a licensed veterinarian. (An antibody product that is currently used by veterinarians to treat clinical signs for WNV, but is not labeled for this use, is HiGamm-Equi; see page 15.)

Elizabeth Davis, DVM, Dipl. ACVIM, assistant professor in equine internal medicine at Kansas State University’s College of Veterinary Medicine, said, “Where I think it’s going to be applicable is in (an exposed) patient that doesn’t have its own circulating antibodies against the virus (unvaccinated or previously unexposed), and we can rapidly administer and help bind some of those virus particles.”

She emphasized the importance of treating the horses early in the course of disease–within the first three days of observing clinical signs (typically neurologic deficits, including ataxia, depression, weakness of limbs, partial paralysis, or muscle twitching). She added that the treatment should not be cost-prohibitive