In Canada, only the Quebec government compensates people who suffer severe injuries from vaccines. The little-known program, a form of no-fault insurance, is held up as a model by public-health officials around the world.

In place since 1986, the compensation plan came about in an unusual way. The parents of Nathalie Lapierre, a girl who contracted encephalitis and suffered severe neurological damage after a measles vaccine, sued the doctor, the vaccine manufacturer and the provincial government.

The case made its way to the Supreme Court of Canada and, in 1985, the claim was rejected.

However, in its ruling, the court said that while there was no legal obligation for the state to compensate, it would be an "excellent thing" to do so.

"What the court said, essentially, is that people exposed to potential harm while undergoing an intervention that is in the greater public good, particularly when it is at the urging of the state, should be compensated by the state," said Yves Robert, a consulting public-health physician with the Quebec Ministry of Health. "It's hard to argue with that logic."

Yet, no other province has followed the Supreme Court's advice, though Manitoba and British Columbia are looking at implementing similar plans.

To date, there have been about 100 claims in Quebec, two dozen of which have been approved. All of those compensated contracted polio from a child who received the oral polio vaccine (a product that stopped being used in Canada in 1996.)

Dr. Robert said there have been claims from flu-shot recipients who developed Guillain Barré syndrome, but they have been rejected because the program is only for those who are permanently disabled. GBS symptoms are almost entirely reversible.

Quebec's vaccine-compensation plan is administered by the Société de l'assurance automobile du Québec, the provincial no-fault automobile insurance program. A person disabled by a reaction to a vaccine is compensated in the same manner as a person injured in a motor-vehicle collision, using actuarial tables of earning potential and medical costs.

But unlike under the auto-insurance plan, those damaged by vaccines retain their ability to take legal action. "You can choose between a no-fault award or a civil suit, but you can't have both," Dr. Robert said.

Some U.S. states have compensation programs for those harmed by vaccines, but they are funded by taxes on vaccines rather than the state.