WASHINGTON (AP) – States will get to decide how to ration scarce vaccine if bird flu triggers a worldwide epidemic, the nation’s health secretary said Tuesday – a decision that means where people live could determine their protection.

“Let’s acknowledge the fact that for the first six months of any pandemic, we’re not going to have a vaccine,” Health and Human Services Secretary Mike Leavitt told The Associated Press.

Once doses start being produced, “This is a battle that’ll be fought in thousands of communities simultaneously. What’s working in one community may not work as well in another,” Leavitt said in a joint interview with Agriculture Secretary Mike Johanns.

The U.S. is girding against the deadly H5N1 strain of bird influenza on two fronts: What to do if this virus one day mutates into a form easily spread among people and makes its way here via ill travelers – and, more immediately, what to do if it wings its way here in a migrating wild bird.

Testing of wild birds, a total of 100,000 by year’s end, has begun in an attempt to catch the virus early if it does arrive that way – with some labs beginning to use a new test that can tell within just four hours if a bird is possibly infected, Johanns said.

The first announced test results could generate false alarms: Influenza is a common infection in birds, and Johanns cautioned that it still will take about a week to confirm whether a suspect bird really has the deadly Asian strain, so-called “highly pathogenic” H5N1 flu.

Johanns said there have been no worrisome discoveries in the testing to date. But it is considered likely that an infected bird could fly to North America as early as this year, perhaps mingling with native birds on breeding grounds in Alaska who, in turn, bring H5N1 south and infect other birds.

Even if that happens, an infected bird isn’t a threat to the average American, but a signal to protect poultry in the area from infection.

“That will not be a crisis,” stressed HHS’ Leavitt.

For people, the bigger concern is watching H5N1 for signs that it’s mutating to become more easily spread. Today, H5N1 is very difficult for people to catch: It has killed at least 127 people worldwide since it began spreading in Asia in late 2003, and on to Africa and Europe in the past year. At the same time, it is blamed for the death or slaughter of some 200 million birds.

The vast majority of the human casualties involved close contact with infected birds or their droppings. Only in a handful of cases have people apparently spread it to each other while caring for sick relatives, the latest an Indonesian family last month that sparked international concern because it was the largest cluster to date.

In case a human pandemic happens, the government is stockpiling both antiflu medication and a small amount of vaccine that might give some protection until inoculations that are a direct genetic match to the illness could be brewed. That will take six months – even longer to produce enough for everyone, Leavitt warned.

Who gets first doses? Vaccine factory employees and front-line health workers head the Bush administration’s list. But scientists are fiercely debating who’s next: school-age children who are flu’s prime spreaders? The frail elderly who may be at highest risk of death? Police, firefighters, utility workers who would have to keep order and essential services running?

Leavitt said supplies will be divided among the states according to their population. It will be up to the states to decide who is first in line.

“You could make a case for many different segments of the community being a priority,” Leavitt said Tuesday. “You could also see different situations in each state that would warrant those decisions being different.”

“The federal government has a very important role, and we’ll play it,” in developing and stockpiling vaccines and drugs, he added. But, “when it comes down to managing the public health in a pandemic situation, it will be up to local public health authorities.”

More sobering, Leavitt said there’s only a very low chance that doctors could contain a human bird-flu outbreak and thus stop a pandemic at its source.

Asia is considered the likely hot zone, largely because there are so many impoverished families who live in close quarters with chickens – not just the back yard but sometimes inside the house – that they need to survive, and thus they won’t willingly slaughter infected flocks.

Leavitt recalled how a health minister in Cambodia told him it was “difficult to get farmers in rural areas to think a few dead chickens are a serious problem” when 14,000 people there died of rabies last year.

The stark reality: “We’ll do all we can to help other nations,” Leavitt said. But if a bird flu outbreak “occurs anywhere in the world, it’s just a matter of weeks before it will be in the United States.”