The Liverpool plant, which Chiron purchased last year, has gone through a series of owners and technical problems in recent years, according to British news reports. In 1999, FDA inspectors accused one of its previous owners, Medeva, of failing to ensure that the plant's systems and equipment for producing Fluvirin were free from contamination.
The following year, British health officials ordered polio vaccines that were manufactured at the plant in 1996 to be withdrawn because of possible contamination with the misformed proteins that cause mad cow disease. And in 2002, Irish officials suspended sales of BCG, a tuberculosis vaccine made at the plant, because of concerns that it was below required strength.
The Chiron vaccine factory in England produces the flu shot. The plant may have contamination problems, which will halt supplies of the vaccine.
(Paul Ellis -- AP)
Medeva was bought in January 2000 by Celltech, which later sold its vaccine business to PowderJect Pharmaceuticals, a British-based firm that in turn sold the plant to Chiron.
"This plant has been well known in the industry," said a British pharmaceutical executive who spoke on condition of anonymity. "It's passed through a lot of companies' hands very quickly. . . . One or two companies who have owned this plant -- perhaps they haven't spent the money on it they should have done, while milking it pretty hard."
Chiron's corporate communications headquarters in Emeryville, Calif., did not return a reporter's phone calls on Friday.
Company officials previously have denied that they sought to expand the plant's production capacity too rapidly and said they had spent $75 million to upgrade the facility.
British health experts said U.S. officials should have realized the potential scale of the plant's problems and taken steps to locate other suppliers.
"The American policy has been cruelly exposed -- their decision to put all their eggs in one basket, so to speak," said John Oxford, an international expert on influenza at Queen Mary's College in London.
"But perhaps this will be a good wake-up call and an encouragement to the American government to think again about how they are going to manage flu. It is urgent that we increase production, because there will be a flu pandemic sometime in future years."
Michael Langman, chairman of the Joint Committee on Vaccination and Immunization, an independent expert advisory committee, said Britain was wise to line up a half-dozen suppliers. "You have to take the approach that it is always possible that something could go wrong with a company's vaccine," he said. "The probability is that it won't, but the possibility is there."
Staff writer David Brown in Washington contributed to this report.