The flu vaccine shortage (search) has set off a scramble to find ways to prevent future repeats of this year's calamity, which has restricted shots to those most at risk.

The recommendations range from the mundane — extending the vaccination season through the winter — to the monumental — spending millions more on research and guaranteeing that the government buys unused flu vaccine to stabilize the volatile market.

Just 10 years ago, five manufacturers produced flu vaccine shots for Americans. That number has dropped to two.

Lester Crawford (search), acting commissioner of the Food and Drug Administration (search), testified before Congress two years ago that he feared the flu vaccine supply network would dwindle to a single company.

That dire prediction effectively came true this year when British regulators announced Oct. 5 that they had shut down Chiron Corp.'s Liverpool production facility. That cut the United States' expected 100 million-dose vaccine supply nearly in half. The FDA, which sent inspectors in early October, agreed that Chiron's 46 million to 48 million flu vaccine doses were not safe.

That has left the United States with 58 million doses from its second supplier, Aventis Pasteur, and scrambling to find more.

The government said its contingency planning began when Chiron first reported contamination problems in late August. Federal vaccine advisers on Oct. 5 quickly prioritized which high-risk individuals should be vaccinated first. The search for additional flu vaccine yielded 2.6 million more doses, announced this week by Aventis.

Health and Human Services Secretary Tommy Thompson, among others, says the government should buy unused flu vaccine doses to guarantee manufacturers produce adequate supplies.

"The guarantee is nice. We'd rather see our vaccine being used," said David J. Williams, Aventis Pasteur president. The company wants to extend flu vaccinations beyond November. The Centers for Disease Control currently recommends people get flu shots in October or November.

Aventis can produce 2 million to 3 million doses of flu vaccine weekly. But it sells few after November.

Thompson said HHS has requested $100 million in the past two budgets to shift flu vaccine production to newer technology. Congress gave the agency $50 million in 2004, but Thompson is lobbying for the full $100 million in the 2005 fiscal year.

The proposal, contained in legislation proposed last year by Sen. Evan Bayh, D-Ind., has languished in committee since last winter. This year's flu vaccine shortage, however, has doubled the bill's co-sponsors.

Williams also wants to vaccinate all Americans to increase flu vaccine demand.

Universal vaccination is an idea championed by a University of Maryland School of Medicine researcher.

"That will, then, force the hand of third-party payers to pay for the vaccine," said James King, a pediatrics professor who tests vaccines. "Unless we make it somewhat cost-effective for the companies to make vaccine, it would be insane for them to make it."

Twenty percent to 50 percent of children get the flu each year, King said, as do 10 percent to 20 percent of adults.

Four decades of research led to the nasal spray vaccine FluMist. Within 10 years, new delivery methods will include flu vaccine delivered by skin patch. Even more options could come if millions more dollars were devoted to research and clinical trials, said Robert Belshe, director of the center for vaccine development at St. Louis University.

Some 36,000 Americans die from flu annually, mortality rates that rise to 51,000 if such flu complications as heart attack and stroke are included, Belshe said.

Stubborn dilemmas linger, including the nuts-and-bolts issue of how to distribute scarce vaccine.

As Chiron insisted contamination was limited to a few million doses of flu vaccine, the Government Accountability Office sounded an early warning.

When flu vaccine was short in 2000, doctors didn't get vaccine first, even though two-thirds of elderly people get flu shots in medical offices.

The GAO "found no indication that the situation would be different if there was a shortage today," the agency told Congress on Sept. 28.

On the distribution question, even the recent pandemic flu plan released in August as a draft "left some of those major decisions unresolved," said Janet Heinrich, GAO's director of health care and public health issues.

"There has been constant discussion ... for five years about how this distribution system would work in a time of shortage," Heinrich said.

Heinrich also said the FDA could avoid a repeat of this year's problems by working more closely with manufacturers to ensure their vaccines are likely to be approved.

The FDA relied on the word of Chiron Corp. that contamination at its Liverpool plant was limited to nine lots. While the agency conducted weekly briefings by telephone, British regulators did an inspection that led them to revoke Chiron's license.

"With Chiron ... the question is how much was FDA involved in actually assisting them in making sure they were in compliance with the good manufacturing practices?" Heinrich said.