Zoo Taking Precautions Against Bird Flu Threat

The San Diego Zoo is preparing to spend at least $500,000 to protect its 3,000 birds, some of which are very rare and found only in captivity, from avian flu.

Officials say past threats, such as exotic Newcastle disease three years ago, have prepared them for the steps to take -- including vaccinating and possibly quarantining birds, and spraying delivery truck undercarriages with disinfectant -- if bird flu reaches the U.S. Officials also would close walk-through aviaries and halt any contact between visitors and birds.