CHICAGO - Perhaps within five years, the government is likely to recommend annual flu shots for every American - not just young children, the elderly and other at-risk people, public health advocates predict.
The government panel that sets U.S. vaccine policy already has begun discussing "universal immunization" as a way to boost vaccination rates and reduce flu-linked sickness and death, Dr. Scott Harper of the federal Centers for Disease Control and Prevention said at a vaccine meeting this week.
The end of a chaotic season where many people seeking flu shots were turned away because of a shortage might seem an odd time to broach the idea of vaccinating even more people.
Harper acknowledged that the recent crisis momentarily upstaged universal immunization discussions, but said it remains a viable proposal.
"Part of our job is to just keep this issue on the radar screen," Harper told vaccine providers, distributors and manufacturers at the national flu vaccine summit here.
The vaccine meeting, held every year, seeks to set an agenda for the upcoming flu season. Participants - many with a financial stake in getting more people vaccinated - said the universal vaccination push is likely to come within the next five years.
The hurdles, some observers say, are daunting.
Unstable supply is one of the biggest. For example, factory contamination problems at Chiron Corp.'s British plant unexpectedly cut the U.S. flu shot supply in half last fall. This year the best case scenario - having about 90 million shots available - isn't even enough for the 180 million high-risk people advised to get shots, let alone the total population of 280 million.
Also, flu vaccine is altered every year because there are always different flu strains circulating. The unused vaccine is discarded at season's end, making flu shots financially unappealing for manufacturers.
So far only one company, Sanofi Pasteur, is licensed to make U.S. flu vaccine for the upcoming season, though public health officials hope two others, including Chiron, will soon gain approval.
Sanofi Pasteur's Philip Hosbach said the company has two idle U.S. factories "because there's not the return on the investment." Universal vaccination could in the long term help stabilize supply if it increased demand, he said.
But Ira Longini, an Emory University biostatistician who specializes in vaccine analysis, said universal vaccination would be unworkable unless supply problems can be resolved.
Demand has historically been a problem, too. Millions of the at-risk patients routinely skip annual shots. Some people worry the vaccine isn't safe or they simply don't like shots, but many also underestimate the seriousness of flu, said Dr. Ann O'Malley, a researcher at the Center for Studying Health System Change.
Estimates suggest that in an average year, flu infects about 82 million people nationwide, hospitalizes 200,000 and kills 36,000.
In recent years the government has repeatedly expanded the list of people who should get flu shots - first to healthy adults over age 50, then to babies and toddlers. That's in addition to traditional groups deemed at risk for flu complications - including adults aged 65 and older, pregnant women, the chronically ill and health care workers.
"It gets confusing because there isn't one consistent message," O'Malley said.
Earlier this year, one medical study suggested the vaccine didn't save lives among elderly people, and some researchers said it might be more effective to vaccinate children, the biggest spreaders of the virus.
Dr. Herb Young of the American Academy of Family Physicians said recommending shots for everyone could ease the confusion - and that his group is moving toward supporting the idea.
"Since family physicians take care of the whole family, it makes a lot of sense," Young said at the meeting. "I'm convinced that we will as a nation eventually end up with it."
On the Net: