State health departments will receive the full amount of their expected flu vaccine (search) orders despite remaining widespread shortages of the vaccine this flu season, government officials say.

A government flu vaccine distribution plan announced Tuesday calls for state authorities to receive approximately 3.1 million doses of vaccine remaining on existing contracts with two major vaccine manufacturers.

Officials intend to apportion 7.2 million more flu vaccine doses to states based on a formula that takes into account how many high-risk patients remain unvaccinated against the flu. Federal authorities are "holding back" an additional 1.3 million doses to stockpile for use in the event of a severe flu emergency this year, says Julie Gerberding, MD, director of the CDC.

The plan "will ensure 100 percent of the public sector orders from the states are completely filled," Gerberding says. Most of the expected remaining flu vaccine doses have not been manufactured but will be shipped as they are turned out by the firm Aventis Pasteur.

But smaller orders of the vaccine from local health departments will go unfilled in favor of the federally run redistribution plan, she says. Federal officials are relying on state authorities to distribute any remaining flu vaccine they receive to doctors, clinics, and nursing homes according to local priorities.

"We see it as the best available solution for getting the remaining vaccine to the people who need it most," says Pat Libby, executive director of the National Association of City and County Health Officials, which helped formulate the plan.

The U.S. flu vaccine supply developed a sudden shortage on Oct. 5 when Chiron Corp. (search) announced it had been barred by British regulators from shipping 48 million expected vaccine doses from its plant in Liverpool, England.

The announcement left the U.S. without about half of its expected flu vaccine supply for the 2004-2005 flu season.

Officials now say they expect to have approximately 61 million doses available for this year, a number insufficient to cover the more than 90 million people deemed at high risk. Those at high risk include people over age 65, chronically ill, infants aged 6 to 23 months, or caregivers who come into close contact with other high-risk people like those with diabetes, kidney disease, or a weakened immune system.

"There's still not enough vaccine for everyone who needs it," says Mary Selecky, secretary of the Washington State Department of Health.

Bush administration health officials are in negotiations with one German and one Canadian vaccine maker in an effort to secure part of about 5 million unclaimed flu vaccine doses.

"We're still working on getting some more vaccine in," Health and Human Services Secretary Tommy G. Thompson told reporters Tuesday.

Meanwhile, the U.S. flu season appears to have gotten off to a slow start. Twenty-nine states have reported flu cases to federal authorities, though none has yet seen widespread flu activity, Gerberding says.

Under Tuesday's distribution plan, states with the most active flu cases will get the flu vaccine first, though the presence of cases will not be factored into calculation for the amount of flu vaccine to be shipped, officials say.

Libby urged unvaccinated high-risk people to contact their doctors' offices or local health departments to check on the availability of the flu vaccine.

"I know this is unsatisfactory for the people who are waiting to know, but I feel this is a fair process," Gerberding says.

By Todd Zwillich, reviewed by Brunilda Nazario, MD

SOURCES: Julie M. Gerberding, MD, director, CDC. Mary Selecky, secretary of health, Washington State. Pat Libby, executive director, National Association of City and County Health Officials. Tommy G. Thompson, secretary of health and human services.