TORONTO - Softening demand for H1N1 vaccine may be spreading to a World Health Organization-led effort to provide developing countries with some pandemic vaccine, a WHO official said Tuesday.

Dr. Marie-Paule Kieny said some recipient countries appear to be reassessing how much donated H1N1 vaccine they want because of shifting perceptions of the benefits of using significant amounts of vaccine at this point.

The WHO had hoped to provide vaccine for up to 10 per cent of the populations of developing countries that wanted donated vaccine. But whether recipient countries want that much vaccine at this point isn't clear, "in view of the trend of the epidemic."

"And it's normal. There is a need for reassessment of what the epidemiology is telling us," Kieny said in an interview from Geneva.

"Of course we cannot rule out that there will be another peak. And we don't know exactly what will happen in the Southern Hemisphere when they start (their next winter) also."

"But many countries now have the impression that the peak is over. And so I think then the governments are also themselves considering whether and how much vaccine they want to deploy."

Even with donated vaccine, deployment isn't cheap. Kieny said it's estimated it will cost between US$1 and US$5 a dose.

"I don't say that this is not needed or this will not be done," she said.

"But I think now that we have a better view, now that we are well into winter in the Northern Hemisphere, we have seen the trend in several countries ... it is the time to reflect and to see how much vaccine will be needed and where."

The first deliveries of donated vaccine are expected to be made this week, roughly two months later than the WHO had initially hoped to start the process. Production problems and the need for extensive legal paperwork contributed to the delay.

Three countries - Afghanistan, Azerbaijan and Mongolia - are set to receive their first deliveries of donated vaccine this week and next.

The first deliveries come at a time when a number of countries have announced plans to sell vaccine surpluses or scale back on their purchases. The Netherlands, Spain, France and Germany are among those that have publicly acknowledged they are looking for ways to deal with unneeded H1N1 vaccine.

The Netherlands has sold surplus vaccine. And in recent days, France has announced it is cancelling more than half of its original order of 94 million doses. Reports suggest France is also negotiating to sell vaccine to countries in the Middle East and Central America.

Meanwhile, Canada has remained silent about what this country will do with an expected large surplus of vaccine.

Government sources said Tuesday that an announcement would be made Wednesday about a portion of the oversupply, though not the bulk of it.

Though a number of developed countries have donated vaccine to the WHO's fund, so far Canada has made no such offer.

The lack of generosity puzzles many who are familiar with the country's long-standing support for the WHO and its over-abundant supply of H1N1 vaccine. Dr. Ross Upshur, head of the University of Toronto's Joint Centre for Bioethics, is among them.

"We may want to ask the question why Canada has A, not had any public discussion of this from our political masters, and B, why it seems that we are not good global citizens in that regard," said Upshur, adding that there is a strong ethical argument for sharing Canada's H1N1 vaccine with other countries.

"We might wonder why Canada is silent on the global stage. But we're prorogued, so we can't have a discussion in Parliament about this," he said, referring to the government's decision to suspend the work of Parliament until March.

"We're effectively cut off from any meaningful public discussion about Canada's global role in H1N1 response because there's no forum for it."

Canada ordered 50.4 million doses of vaccine in August, when it was still assumed people would need two doses of vaccine apiece to be protected. Studies later showed one dose per person was adequate.

Other unforeseeable factors have contributed to the excess here and in other countries that pre-ordered vaccine.

The pandemic has remained relatively mild, a fact that has meant many people feel safe forgoing an H1N1 shot.

The vaccine proved difficult to make, which meant supplies arrived later than planners had hoped. And the fall wave started early, so by the time large amounts of vaccine were available, flu activity was nearing or past its peak in many places - further contributing to a sense in some quarters that getting vaccination was no longer necessary.

The Public Health Agency of Canada estimates somewhere between 40 and 45 per cent of Canadians have been vaccinated against H1N1, a rate that is among the highest in the world. But that still leaves the country with upwards of 30 million doses of vaccine that haven't been claimed.