For a second year, federal health officials plan to urge the elderly and others most at risk from the flu to be the first vaccinated this fall — just in case of shortages.
"We want the flu shot in their arms first," Dr. Julie Gerberding, head of the Centers for Disease Control and Prevention, told members of Congress on Wednesday.
It's too soon to predict just how much flu vaccine the nation will have. But after last year's surprise shortage, the CDC is making plans for a worst-case scenario in which this year mirrors last.
If there's plenty of vaccine, the CDC will tell healthier people to roll up their sleeves.
People will "have to pay attention because the message will evolve," Gerberding told a House Energy and Commerce subcommittee.
High-risk people include those 65 or older, nursing home residents, anyone with a chronic condition such as heart or lung disease, babies and toddlers ages 6-23 months, pregnant women, and health care workers who care for high-risk patients.
Last October, the nation's flu-shot supply was abruptly cut in half when British regulators shut down a Chiron Corp. factory because of contamination concerns.
The CDC urged healthier adults to forego shots so the youngest, oldest and sickest could get them. That effort, and a mild flu season, meant that 57 million people ultimately were vaccinated, Gerberding said. About 3 million shots went unused.
In addition to the worst-case scenario, in which the nation gets only 53 million doses of vaccine, the CDC is also preparing for two other possibilities:
The nation has never administered more than 83 million flu shots in a single year, even though 185 million people are considered high-risk. Many people who need a shot either don't realize it or don't want it. About 63 percent of the elderly got their shots last year, for example, almost as many as in years when supply is ample, CDC said.
Sanofi-Pasteur remains the nation's leading flu shot provider, with an estimated 50 million to 60 million doses planned for this fall.
Chiron could provide about 25 million shots, but first it must complete changes at its Liverpool, England, factory to ensure the vaccine's sterility.
Chiron has made substantial progress, said FDA vaccine chief Dr. Jesse Goodman, who visited the factory last week. But, "it's too soon to tell" if the fixes will be complete in time for flu season.
The FDA also is working with GlaxoSmithKline in its bid to become the nation's fourth flu vaccine supplier.
Glaxo, which has long sold flu shots in other countries, could provide 10 million additional flu shots, but first it must file for and receive an FDA license, Goodman said. That filing is to happen soon.
Some 3 million doses of a nasal-spray vaccine that's for use only by healthy people, MedImmune Inc.'s FluMist, also are anticipated.