London (CNSNews.com) - The U.K. government was heavily criticised Tuesday after an American research organization alleged that Britain bought the wrong type of smallpox vaccine to protect the country from a terrorist attack.

The Arlington, Va.-based Potomac Institute raised doubts about the Lister strain of vaccine purchased by the British government, saying it might not be as effective as a strain developed by the New York City Board of Health.

The institute's scientists say the New York vaccine, used by the American government, is effective against a type of smallpox that is most likely to be used by terrorists and that the Lister vaccine might not provide the same protection against the strain.

Dr. Steve Prior of the Potomac Institute said the New York vaccine battled smallpox in India, the source of bio-weapons developed after the disease was eradicated worldwide. The Indian strain is thought to have been obtained by Iraq.

"When you are making decisions of this magnitude, you cannot afford to make the wrong one and you certainly cannot afford to make it for the wrong reasons ... I think it is indefensible," Prior told reporters.

"There will not be a second chance to get this right," Prior said.

The U.S. government is buying more than 209 million doses of the New York vaccine from Acambis, a company based in Cambridge, England. U.S. officials are currently considering whether to vaccinate all Americans or to focus on emergency and initial-response workers.

The controversy was heightened by the revelation that the chief executive of the corporation contracted to produce the vaccine, Powderject Pharmaceuticals, recently donated about $75,000 to Prime Minister Tony Blair's Labor Party. The $45 million contract to produce additional doses of the smallpox vaccine was handed out after a process that opposition parties say was shrouded in secrecy.

A Powderject spokeswoman said the donation was "well-documented." The decision about which strain of vaccine to purchase was entirely separate from the contribution by CEO Paul Drayson and the subsequent awarding of the contract, the spokeswoman said.

The Department of Health (DoH) backed up that assertion, pointing out that the decision to use the Lister vaccine was part of a process separate from the awarding of the vaccine contract.

"The decision to purchase the Lister strain was based on expert scientific and medical advice available to the Department of Health, including the Ministry of Defence, with whom we are collaborating," the spokesman said. "The Lister strain is also the strain chosen by our European partners."

The department defended its decisions and said the Lister vaccine has been stringently challenged in the field by the more severe form of smallpox, variola major, but said it could not make the full reasoning behind its decision known.

"There are obvious national security ramifications surrounding decisions made to protect the public from terrorist attack," the DoH spokesman said.

The Potomac Institute research sparked an angry reaction from opposition politicians.

"It is imperative that we have a full independent inquiry into the whole sordid affair of the smallpox scandal," said Dr. Liam Fox, health spokesman for the Conservative Party. "The public will wonder if there is any level of incompetence that warrants a firing in Tony Blair's administration."

"If reports are correct, that the government has purchased the wrong vaccine, then that is not only incompetence on a monumental scale but the fact that the contract was given to a middle man who had given a huge donation to the Labor Party ... is a national scandal," Fox said.

"If these allegations are true, heads must roll," he said.

Dr. Evan Harris, health spokesman for the third-party Liberal Democrats, said it was "very worrying" that the vaccine advice process in Britain was kept secret and that unlike in the United States, there was no public tendering process for the smallpox contract.

"The government seems unable to understand that the smallpox vaccine chosen is scientifically contentious," Harris said. "The fact that it was bought from a company owned by a Labor donor only strengthens the need for the government to be open and transparent about the decision, and the reasons for it."

The administration was also criticized by some members of Blair's own party.

Labor MP Ian Gibson, chairman of the parliamentary science and technology committee, called on the government to be more open about how it choose to purchase the Lister strain.

"We have no idea how this decision was made and I think we ought to know," Gibson said by phone from his constituency office in eastern England. "I don't understand how they came to this particular conclusion."

E-mail a news tip to Mike Wendling.

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