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Rocky Mountain News, CO Animal illnesses a signal to man Veterinarian urges health agencies, zoos to cooperate By Bill Scanlon, Rocky Mountain News July 19, 2003 Humans: Ignore the diseases of prairie dogs, monkeys and crows at your own peril, the nation's veterinarians warn. Animals carry clues to the diseases that will ravage humans a month, a year or a decade from now, but few people are listening, says Tracey McNamara, the veterinary pathologist who in 1999 was the first to link the dead birds at the Bronx Zoo to a new human encephalitis that turned out to come from West Nile virus. McNamara, former head of pathology for zoos in New York, is one of the speakers at the American Veterinary Medical Association's annual meeting today through Wednesday at the Colorado Convention Center in Denver. Nine thousand are expected to attend. In 1999, McNamara recalled, "I had a barrel full of dead birds with encephalitis, but there was a disbelief that there could be a link between birds and humans." Finally, an electron microscopy of a a dead flamingo showed that it had encephalitis, just like humans showing up in New York hospitals were displaying. "We knew we'd made history," said McNamara, who last year won the association's President's Award for bridging the veterinarian and public health arenas. Back in 1999, many experts thought West Nile would be a one-summer phenomenon. Instead, it has swept across the nation and is now found in 38 states. "West Nile is here to stay," McNamara predicts, noting that unlike most viruses, it can infect numerous species. "I can't think of another virus that can kill both alligators and birds, dogs and horses, cold-blooded animals and warm- blooded animals. How do you predict what's going to happen with this virus?" West Nile virus is named after a province in Uganda where a woman first got sick with a new virus in 1937. The strain identified in New York in 1999 is somewhat different, and that confused doctors for a while. They thought St. Louis encephalitis was making people sick on the Eastern Seaboard. "But St. Louis (encephalitis) doesn't kill birds," McNamara said. "Just as human docs recognized that this is something unusual, the fact that crows were dropping from the sky made it hard to miss." A cataloguing of all the animals exposed to West Nile found, disturbingly, that some showed signs of brain swelling, or encephalitis, eight months after they had supposedly recovered. Very recently, people known to have contracted West Nile virus are displaying Parkinson's disease-type tremors, something first spotted in the zoo animals in New York, McNamara said. Her push, and that of many veterinarians, is to get zoos and aquariums to work together with public health departments. "There are many parallels between birds and humans," McNamara said, noting that a polio-type attack on the cells of the spinal cord is a byproduct of West Nile in both. Animals have shorter life spans, so autopsies can be done much more often, bringing insights into diseases that cross species. Doctors tend to be comfortable with the familiar, looking to known diseases for answers, McNamara said. But zoological pathologists are more comfortable with the unknown, ready to seek answers from rare or never-before-seen diseases. McNamara gives credit to the Centers for Disease Control and Prevention's Fort Collins lab for creating a partnership for surveying West Nile virus at zoos. "It closed the gap that existed between zoos and wildlife people and the public health community." West Nile gave everyone a kick in the pants to think outside the box, and that's a good thing because it's only the beginning, McNamara said. Worldwide air travel and increasing population guarantees an accelerated outbreak of mosquito-borne diseases, McNamara said. "Human outbreaks will become increasingly severe. "Things are evolving so quickly," she added. "This year, we've had monkeypox and SARS," she said, referring to the pox that originated in Africa and spread through exotic prairie dogs to the Midwest, and to sudden acute respiratory syndrome that has killed dozens in Singapore, China and Toronto. "Monkeypox wasn't diagnosed until people got sick," McNamara said. "Wouldn't it be preferable to find it in prairie dogs? Instead, she said, "We are still using taxpayers as sentinels." She noted that there's a vaccine against West Nile for horses, but not yet for people, although human trials could begin as early as late summer. "It's in everyone's best interest to define new diseases as quickly as possible because there are going to be many more coming down the turnpike." Seventy percent of the known bioterrorism threats are agents that also can make animals sick, and that usually do so first. Among them are anthrax, encephalitis, eastern equine encephalitis, botulism, tularemia, plague and brucellosis. "We need to know about the first case, not the 100th case. If it's a disease that shows up first in animals, we'd prefer to know about it in animals before people present in emergency rooms." She added: "We need a better technology transfer. We need an ability to rapidly screen large samples to search for bioterrorism threat agents." The veterinary meeting will include talks on monkeypox and on a follow-up medical study done on the search-and-rescue dogs at the World Trade Center. scanlon@RockyMountain News.com or (303) 892-2897 SOURCE: Rocky Mountain News, CO http://rockymountainnews.com/drmn/local/article/0,1299,DRMN_15_2120440,00.html * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn