If you're young and healthy, don't expect a flu shot this year.

Americans' supply of flu vaccine was cut in half Tuesday when Britain shut down a major supplier just as the flu season is about to begin.

The Bush administration urged the public and doctors to begin a voluntary rationing of the roughly 54 million flu shots that will be available this year.

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

The announcements came less than two weeks after top U.S. health officials said they didn't expect flu vaccine shortages.

The Lincoln-Lancaster County Health Department and a local hospital on Tuesday tried to figure out how to deal with the shortage. 

"This is not a local problem, this is a national problem," said Tim Timmons, communicable disease program supervisor of the health department.

They scrambled after Chiron Corp., the world's second-leading flu vaccine supplier, announced it wouldn't supply 50 million doses of flu vaccine to the United States.

Citing manufacturing problems at an English factory where the company makes its Fluvirin vaccine, British regulators suspended Chiron's license for three months.

No Fluvirin will be shipped anywhere this year, the company said.

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

The U.S. government urged voluntary rationing during a shortage in 2000, but never before has the nation lost half its supply.

Because so many groups order flu vaccine, it wasn't known how much of Nebraska's supply could be lost, said Dr. JoAnn Schaefer, the state's deputy chief medical officer.

But the Lancaster County Health Department won't get the 5,000 Fluvirin doses it ordered, Timmons said.

Saint Elizabeth Regional Medical Center won't get its 5,200 doses, either.

Both BryanLGH Medical Centers in Lincoln fared better —  they already received the nearly 6,000 doses they ordered from Aventis Pasteur, said spokeswoman Deb Hartman. 

Aventis is the world's leading supplier of flu vaccines.

Only Aventis and Chiron Corp. were making flu shots for the United States this year.

Saint Elizabeth has 160 doses of Aventis pediatric vaccine for children up to 35 months old, said  Kurt Clyne,the hospital's pharmacy director.

The health department has 500 doses of Aventis vaccine, but is waiting to see what the federal Centers for Disease Control and Prevention says to do before giving out these doses. 

The department ordered 2,000 Aventis doses that should have arrived this month, Timmons said.

Whether these doses actually will get here was unknown Tuesday said Timmons.

Last year, the department gave out 7,500 doses, which wasn't enough to meet local demand.  

It takes six to nine months to make flu vaccines, so there's no way local officials can be ready for the flu season, Timmons said.

Flu shots usually begin in the next week or so before the flu season, which usually runs from November through March, with the heaviest months being December, January and February.

The flu hit early last year in Nebraska, prompting many people to get vaccinated early and exhausting the supply in many parts of the state.

That outbreak was described as the worst in at least eight years.

Health officials are working on distribution  solutions. 

The CDC has asked Aventis to try to redistribute its shipments so high-risk patients get shots first.

Officials also were working to learn whether Aventis' vaccine could be diluted to get two doses out of each original shot, but the Food and Drug Administration said it was too early to know whether the agency would allow such a move.

Aventis already had said it didn't expect to be able to produce more vaccine until at least November, when existing orders are filled.

In an average year, the flu kills 36,000 people and hospitalizes 114,000 more, most of them elderly.

Reach Leah Thorsen at 473-7246 or lthorsen@journalstar.com. The Associated Press contributed to this report.