Horsetalk.co.nz Horse owners urged to vaccinate to reduce toll of West Nile virus
Greater efforts are needed to encourage Kentucky’s horse owners to vaccinate against West Nile virus if continued losses from the infection are to be reduced or even eliminated, Professor Peter Timoney says.
Until 1999, West Nile virus was unknown in the Western Hemisphere, much less the United States.
In August of that year, the virus was identified in New York City and caused the deaths of seven persons from viral encephalitis (brain inflammation).
Coincidentally, the virus was also implicated in the death of birds in New York’s Bronx Zoo and crows in the precincts of the zoo.
It is not surprising that equine herpesvirus 1 (EHV-1) is so well adapted to infect horses.
Professor Peter Timoney, with the Maxwell H. Gluck Equine Research Center at the University of Kentucky, says EHV-1 is believed to have co-evolved with horses over millions of years.
This co-evolutionary relationship resulted in the development of a life-long carrier state in a high percentage of infected horses. This involves viral latency (silent infection) of various sites (the trigeminal ganglia in the central nervous system, respiratory lymphoid tissues, and CD3+ T lymphocytes in the blood).
Latency ensures the perpetuation of EHV-1 by serving as a virus reservoir for infection and dissemination in susceptible populations.
AAEP Publishes Epizootic Lymphangitis Guidelines Sponsored by:
The American Association of Equine Practitioners (AAEP) has published on its website comprehensive guidelines to assist practitioners and regulatory agencies with identification, diagnosis and control of epizootic lymphangitis, a contagious, chronic granulomatous disease of the skin, lymphatic vessels and nodes of the limbs, neck and chest of horses and other equid species.
Although epizootic lymphangitis is not known to occur in horses in the United States, the disease is common in parts of Africa, the Middle East, Russia and Asia, where it is responsible for significant morbidity with chronic weight loss and progressive debility in affected animals.