BOSTON -- There are new concerns over a major shortage of the flu vaccine this season.

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Liz Brunner Reports On Vaccine

NewsCenter 5's Liz Brunner reported that the British government found problems with the manufacturing plant responsible for half the U.S. vaccine supply.

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Doctors are already figuring out what they'll tell anxious patients who will start demanding a flu shot before supplies run out, but patients at most risk will get the existing flu shots first.

Many doctors' offices, like Needham Pediatrics, already have hundreds of doses of flu vaccine on hand and are giving shots to high-risk patients.

But the closing of the British lab that makes Fluviron translates into a shortfall of 48 million doses in the United States. The state of Massachusetts had ordered almost 500,000 shots from the company.

The federal government is considering options, such as cutting doses in half and strict rationing.

"The thing you can do immediately is to be very careful regarding your prioritization -- make strict guidelines that the highest risk people get the vaccine first," said Dr. Anthony Fauci, of the National Institutes of Health.

Those considered at highest risk include: people over 50; younger people with chronic medical conditions like asthma and diabetes; those with compromised immune systems; pregnant women in the second and third trimesters; and very young children between the ages of 6 months and two years.

Jill Newman and her daughter, Chloe, had the flu last year -- that's why they signed up to get their shots now.

"She had extraordinary high fever of over 105 for nine days -- in and out of the doctor, in and out of the hospital," said Jill Newman.

Doctors stress there's no reason to panic if you can't get a flu shot this year, and the vast majority of healthy people who contract the disease weather it just fine.

"They'll be miserable for a few days. It's a bad respiratory illness with aches and pains. By and large, the greater majority of healthy people, including children, will recover without complications," said Dr. Norman Rosin, of Needham Pediatrics.

The shortage may make more people choose a nasal flu vaccine called FluMist -- which is not widely used now because insurance companies won't pay for it.