But some airline workers and health experts see shortfalls in planning and recommend additional steps they say could save lives and help a financially fragile industry fly through a potential nightmare.
The Bush administration hopes quick action can contain any U.S. outbreak and has not ruled out travel restrictions.
Federal health officials have authority to detain or isolate any airline passenger suspected of harboring the avian flu virus, which scientists fear could mutate to leap from person to person and quickly spread globally.
Air travel was crucial in spreading the deadly Severe Acute Respiratory Syndrome, or
SARS, virus around Asia and to Canada in 2003. SARS ended up killing around 800 people globally before it was contained.
SARS was harder to catch than the flu and, unlike influenza, only spread after patients began showing symptoms, but airlines and health officials are basing some bird flu preparations on the SARS experience.
The U.S. Centers for Disease Control and Prevention has increased the number of quarantine centers at big airports and land crossings from eight in 2003 to 18 now, partly due to the bird flu threat.
There are plans to expand to 25 centers, depending on resources and need, said Ram Koppaka, chief of the
CDC's quarantine and border health division.
Pacific entry points, including Hawaii, Los Angeles, San Francisco and Seattle, are emphasized.
The H5N1 virus is entrenched in poultry flocks in much of Asia. It has infected more than 120 people, killing at 64 people in Indonesia, Vietnam, Thailand and Cambodia in two years.
U.S. health officials are also working with airlines to review the cleaning of plane interiors and the handling of passengers with signs of viral illness.
"At this point we are comfortable with our relationship with the CDC and confident that they will inform us if the situation changes that mandates a different approach," said Katherine Andrus, assistant general counsel for the Air Transport Association, the lead U.S. airline trade group.
HARD TO SPOT INFECTION
International travel on all carriers to and from the United States for 2005 was forecast at 137 million people, government estimates show. About 16 percent were on Pacific flights. U.S. airlines handle about half the traffic.
But Georges Benjamin, executive director of the
American Public Health Association who led a recent CDC-sponsored study of quarantine planning, said a more robust approach is needed.
The difficulty of quickly locating passengers who may have been exposed to infectious agents posed a "significant" gap in the quarantine system, the study concluded.
The report supported traveler cards embedded with personal contact data and flight and seat information to help locate people. It also found that CDC is stretched thin and there was no single organization within the government with the authority and the resources to coordinate quarantine responsibilities.
The CDC works with with border control, human services and local health agencies.
The Professional Flight Attendants Association at Northwest Airlines wants lawmakers to mandate that carriers keep planes properly ventilated on the ground and provide early access to antiviral drugs or a bird flu vaccine -- if health authorities turn to either.
Bankrupt Northwest, a big U.S. carrier to Asia, referred questions on its plans to the Air Transport Association.