TORONTO - The United States began to vaccinate its citizens against swine flu on Monday, one of the first countries to roll out its portion of what may be an unprecedented effort to immunize upwards of a billion people around the world over the next few months.
Health-care workers in a Memphis, Tenn., hospital were among the first in the U.S. to receive the vaccine, which is currently only available in the U.S. in nasal spray form. Injectable vaccine is expected to start flowing out of the production pipeline soon.
With substantial H1N1 activity in the U.S. at present, officials are relieved vaccine is starting to become available five months after the new virus was first detected.
The relief is tempered, however, with the knowledge that the coming weeks will be challenging at best, given the difficulties of getting still limited amounts of vaccine to the people who want it. If things go badly, they know, the reputations of flu shots specifically and vaccines in general could take a beating.
"I think it will be tough," predicted Dr. Paul Offit, chief of infectious diseases at Children's Hospital of Philadelphia and a key figure in the pro-vaccination movement.
Dr. Anne Schuchat, director of the national centre for immunization and respiratory diseases at the U.S. Centers for Disease Control, agreed.
"I think that the positive impact of a successful program could be huge. And the unintended consequences of problems in the program would also be huge," Schuchat admitted.
"So I think that public health and the health-care system do feel a lot of pressure in trying to make this go as smoothly as possible. And then on top of that we do have this race against the virus, which is continuing to cause disease around the world."
The U.S. is not the first to begin to vaccinate; China began a few weeks ago. And Australia started to offer pandemic flu shots last week.
Canada is currently only scheduled to begin vaccinating in early to mid November, though Chief Public Health Officer Dr. David Butler-Jones has said he could ask Health Canada to release the vaccine a few weeks earlier under special licensing provisions if the risk from the virus seemed to increase.
Eventually, the World Health Organization has predicted, three billion doses of the new H1N1 vaccine could be produced over 12 months. It remains unclear whether global delivery systems are in place to administer so many doses. It's also unclear whether there is that much demand for vaccine against this relatively mild pandemic strain.
In the U.S. and Canada, poll after poll shows somewhere around half the population -- sometimes less -- plans to get a flu shot. While that's better than the uptake rate for seasonal flu vaccine -- last year just under 30 per cent of Canadians over age 12 got a flu shot -- it is not as high as officials would like to see.
Dr. Michael Osterholm, an infectious diseases expert at the University of Minnesota, said the population at this point breaks down into three groups: Those who are eager to get the vaccine and who will be annoyed by any delay; those who are undecided about whether to get it and who plan to watch how the roll out unfolds before making up their minds; and those who either reject vaccines in general or flu vaccines specifically.
Any signs of adverse reactions that might be linked to the vaccine will drive away the second group, said Osterholm, who is director of the university's Center for Infectious Diseases Research and Policy.
And Offit said the third group will jump at the opportunity to discredit the vaccine if and when such events arise. He admitted that prospect has the pro-vaccine forces essentially holding their collective breath.
"Of course," Offit said. "Because I think when the anti-vaccine groups get a hold of something, they're very good at it."
"They're very good at public relations. They understand how to get the ear of the media and how to get the ear of Congress."
Schuchat and colleagues at the CDC have been trying to inoculate the program against the impact of that kind of event, warning that even though these vaccines should be as safe as seasonal flu shots, things will happen once mass vaccination starts. Pregnant women will miscarry. People will have heart attacks. Rare neurological disorders may occur.
But these things happen all the time among people who haven't just received a flu shot. Determining whether the events were caused in some way by the vaccine or -- as experts think is more likely -- are mere coincidences will be critical. Unfortunately, the work needed to answer those questions takes time.
"If we detect a signal we'll need to investigate it carefully and even with rapid investigation, it may take some time," Schuchat said.
"I think that patience is a hard thing to have when there's disease around us or vaccination needs to occur quickly. So I think expectations about how quickly we'll be able to understand signals -- that's a tricky issue."
Osterholm said the situation is made more difficult still by the fact that there will be glitches in distribution and the fact that no one knows what is going to happen with the virus.
If there appears to be an increase in reports of deaths among children and pregnant women, demand will rise, he predicted. But if severe cases remain rare and the illness is perceived as mild, people could decide to take a pass.
"We're not quite in Never Never Land, but we are charting previously uncharted waters, because of all these issues," Osterholm said.
