* Senators ask why HHS made promises
* Novartis, CSL working to improve production
* Vaccine shortage could drive demand
By Maggie Fox, Health and Science Editor
WASHINGTON, Oct 27 (Reuters) - The U.S. government may end up throwing away unused doses of swine flu vaccine if people cannot get it soon enough, the director of the U.S. Centers for Disease Control and Prevention said on Tuesday.
Members of Congress questioned whether federal officials were too rosy in their estimates of how much vaccine would be available and when, and companies said they were still struggling to produce immunizations against H1N1.
CDC director Dr. Thomas Frieden said 22.4 million doses were now available to states, which can get them a day after they order them.
“It’s quite likely that that too little vaccine is one of the things that’s making people more interested in getting vaccinated, frankly,” Frieden told reporters.
“We think it will get easier to find vaccine in the weeks that come.”
Many states and cities say they have received about one-tenth as much vaccine as they originally had expected by this time. Frieden said the delays may discourage people who are lining up for vaccine.
“It is likely also as we produce more vaccine and as both people are given the opportunity to get vaccinated, and as disease maybe wanes in the future, we will have significant amounts of vaccine that can’t be used,” Frieden said.
“One of the messages for states, localities and health providers is not to reserve vaccine that they have available, to give it out as soon as it comes in, because more is on the way.”
In September, U.S. officials said 40 million vaccine doses would be available by the end of October and they estimated 20 million doses a week would be delivered, with a goal of 250 million doses by the end of flu season in March or April.
Maine Republican Senator Susan Collins asked why the estimates were so far off.
“It now appears that much of the vaccine could arrive only after many people have already been infected with H1N1,” she said in a letter to Health and Human Services Secretary Kathleen Sebelius, released late on Monday.
“It seems that HHS gave its assurance of sufficient supply in August without adequate information to make such a commitment.”
Connecticut independent Senator Joseph Lieberman weighed in on Tuesday.
“Unfortunately, these missteps in estimating available doses of H1N1 vaccine have effects beyond just growing public frustration; they have the potential to critically undermine our vaccine distribution efforts, which depend on accurate estimates of vaccine availability,” he said.
But HHS spokeswoman Jenny Backus said the agency was simply passing on information as it became available.
“We have been very clear and open and told the American people what we know when we know it,” she said in a telephone interview.
“We have passed on the manufacturing estimates, and as they have changed, we have conveyed the information to the American people, too.”
Vaccine makers and government researchers alike have complained about the reliance on outdated and unpredictable vaccine manufacturing methods that use chicken eggs.
The virus has spread much faster than vaccine can be delivered, and Frieden estimates that millions of Americans have been infected. While not especially deadly, it is affecting young adults and children who normally escape the most serious consequences of seasonal flu.
Editing by Cynthia Osterman