Healthy adults will be asked to delay or skip getting flu shots this year so doctors can give priority to more vulnerable patients, Dr. Gregory Poland of the Mayo Clinic said after an emergency meeting of the government's vaccine advisers, who unanimously endorsed the voluntary rationing.

"We will need the help of the public, the public health community and the medical community to make sure that the vaccine goes to those who truly need it most," said a statement from the Department of Health and Human Services.

The people most in need of flu vaccine are babies and toddlers ages 6-23 months; the elderly; anyone with chronic conditions such as heart or lung disease; and pregnant women.

As a result of today's announcement of a flu vaccine shortage, health officials in Hawai'i this morning recommended that healthy people postpone flu shots to leave them for those most vulnerable to the seasonal disease while authorities evaluate what to do next.

British regulators suspended the license of Chiron Corp., the world's second-leading flu vaccine supplier, for three months. They cited manufacturing problems at the factory in Liverpool, England, where Chiron makes its leading Fluvirin flu vaccine.

Hawai'i Health Department officials were consulting with the federal Centers for Disease Control and Prevention this morning. State immunization educator Judy Strait-Jones said that the shortage created by the production shutdown by Chiron — the nation's biggest supplier of flu vaccine — will alter advice given as this traditional flu-shot season was just beginning to gear up.

"Locally, we are asking for the help of every person out there," Strait-Jones said. "Pay attention and only those who are at high risk should get that vaccine."

Thousands of Hawai'i residents get their annual flu shots through community clinics sponsored statewide by an HMSA subsidiary. On O'ahu, those clinics began last week and were scheduled to continue each week through December. They were expected to begin on the Neighbor Islands later this week and continue through November.

HMSA senior vice president Cliff Cisco said it's not clear if those community clinics will continue because of the expected shortage.

He said HMSA — the state's largest health-care insurer — had expected to get the majority of its vaccine supply from Chiron. "We're trying to determine what we do next," Cisco said. "We certainly won't find enough to replace what we had on order from Chiron."

"We are currently evaluating our options including how to proceed with any previously scheduled community clinics," Cisco said.

The sanction against Chrion means more than a delay, Chiron officials said: They will ship no Fluvirin anywhere this year, including the 46 million to 48 million doses originally planned for the United States.

"This season is gone," said Chiron chief executive Howard Pien.

The rest of the nation's supply, roughly 54 million flu shots, is coming from Aventis Pasteur, the world's leading supplier.

Aventis already had said it didn't expect to be able to produce more until at least November, when existing orders are filled. But the Centers for Disease Control and Prevention has now asked Aventis to try to redistribute its shipments so high-risk patients get their shots first, CDC chief Julie Gerberding said.

"We'll be working on this fast and furiously," she told lawmakers before racing out of a House hearing to deal with today's surprise announcement.

High-risk patients depend on flu shots because the injections are made of killed influenza virus. For other people, there is another option: About 1 million doses of an inhaled flu vaccine, MedImmune Inc.'s FluMist, will be available for healthy 5- to 49-year-olds. It's made from live but weakened influenza virus.

Also under consideration: Whether Aventis' vaccine could be diluted to get two doses out of each original shot. Dr. Anthony Fauci, infectious disease chief for the National Institutes of Health, said a small study a few years ago suggested doing so would provide enough protection.

Chiron's shipments already had been delayed by a contamination problem discovered in August. The company, based in Emeryville, Calif., has insisted only 4 million doses were tainted, although it refuses to identify the contaminant.

Less than two weeks ago, U.S. health officials assured the public that FDA monitoring of the rest of the supply showed it was fine and there would be no shortage.

British officials didn't explain why they disagreed.

Flu shot campaigns usually start in October, a month before the flu season typically begins in the United States. In an average year, flu kills 36,000 people and hospitalizes another 114,000, mostly the elderly.

Other countries likely will face shortages, too, said Dr. Klaus Stohr, the World Health Organization's influenza chief.