The Scientist

The organization representing U.S. zoos and aquariums recently released a set of guidelines for monitoring and preventing avian influenza within their walls. As part of the measure, American Zoo and Aquarium Association (AZA) officials suggest isolating and decontaminating areas if they become affected by the flu, and eventually closing certain facilities.

"Even if we never see avian influenza in this country, this is a good thing to be doing," Donald Janssen, associate director of veterinary services at the San Diego Wild Animal Park, who helped draft the recommendations, told The Scientist. "But in all likelihood, in some form or another, we will see the high pathogen strain of avian influenza H5N1."

Robert Cook, chief veterinarian and vice president of the Wildlife Conservation Society -- which operates five parks in New York City -- noted that avian flu could hit U.S. zoos though birds or people, although the latter possibility was much less likely. Cook also urged calm. "It's very possible that avian flu won't come," he said.

Even if avian flu hits zoo birds, "it is very unlikely, almost impossible, that a visitor will get infected in a zoo," Mike Cranfield, director of animal health, research, and conservation at the Maryland Zoo in Baltimore, told The Scientist. He noted that the risk of infection was higher in zoo workers, but even they are relatively safe because of the low density of zoo birds -- relative to chicken farms, for instance.

The proposed measures include education programs for employees at the 210 AZA-accredited zoos and aquariums, along with instructions for wearing appropriate equipment and employing proper cleaning and disinfecting protocols. In the event of an outbreak, the AZA suggests developing protocols for short-term treatment of affected native birds and moving indoors collection of birds that co-mingle with free-ranging waterfowl. The organization also recommends that zoos consider vaccination of birds if there is a threat of an outbreak.

The guidelines emphasize biological containment, which Cranfield said is an "excellent" approach. "If the flu comes, it is going to take citywide, statewide, and countrywide efforts to fight it. We will have to develop our own little in-house plan and that will have to fit into a much bigger plan," he said.

Cook, who sits on the animal health committee of the AZA, noted that the guidelines were written with the input of zoo veterinarians in the U.S. who had years of experience in dealing with preventing disease in zoo collections and protecting visitors' health. He added that guideline writers had experience with other outbreaks, such as West Nile virus in the U.S., and also studied the experience of places like the Jurong Birdpark in Singapore, which had to confront a threat of avian influenza last year.

Jonathan Sleeman of the Virginia Department of Game and Inland Fisheries told The Scientist he is "very impressed" with the recommendations, and praises the AZA for being so proactive on this issue. Still, he said he wonders how well member institutions will be able to comply with the guidelines, given that they are recommendations, not regulations. For instance, Sleeman noted that the AZA recommended that institutions develop a protocol for proper footbath preparation, maintenance, and disposal -- but don't specify a disinfectant to use, how often to change it, and where to dispose of the materials.

Jane Ballantine, AZA spokesperson, told The Scientist that the guidelines were left open-ended to give facilities with different species the chance to personalize them. "We have to make certain that the information and materials we issue can be adapted by our members to fit their particular situations."

"If things change, we'll surely need to update these guidelines, said San Diego's Janssen. "For now, they provide another standard for the protection of our bird collections from a variety of infectious diseases."