01:00 AM EST on Saturday, January 14, 2006

Influenza A (H5N1) has been identified in birds in: Cambodia, China, Croatia, Hong Kong, Indonesia, Japan, Kazakhstan, Korea, Laos, Malaysia, Mongolia, Philippines, Romania, Russia, Thailand, Turkey, Ukraine, and Vietnam.

Since 2003, the World Health Organization has confirmed 161 cases of human infection with the virus, and 79 deaths. Human cases have been reported in Cambodia, China, Indonesia, Thailand, Turkey and Vietnam.

So far all the sick people appear to have acquired the infections from birds. There is no evidence of person-to-person transmission.

But if the virus mutates into a form that is easily transmissible to people, and if it proves as severe as the 1918 Spanish flu:

The pandemic will reach U.S. shores within 30 days.

Within nine weeks, 37 million Americans will be sick.

By the 12th week, 90 million will have fallen ill.

The pandemic will peak in week 16, with 92 million sick.

Illness rates will be highest among school-age children: 40 percent.

20 percent of working adults will get sick.

50 percent of sick people will seek medical care.

9.9 million will need hospitalization, with 1.5 million in intensive care.

1.9 million will die

In each community, the outbreak will last 6 to 8 weeks.

Multiple waves of illness could occur over a year and to 18 months.

Sources: U.S. Department of Health and Human Services; World Health Organization; World Organisation for Animal Health