(AP) -- The U.S. won't have nearly as much swine flu vaccine ready by mid-October as long predicted - 45 million doses instead of the anticipated 120 million, a federal official said Monday.
It's not a shortage but a delay, Health and Human Services spokesman Bill Hall said. More will arrive rapidly after that, with about 20 million more doses being shipped weekly until the government reaches the full 195 million doses ordered, he said.
But the October shortfall, blamed on manufacturing issues, will extend by a month efforts to get people at highest risk vaccinated against the new flu strain. First in line are supposed to be pregnant women, children and health care workers, followed by younger adults with flu-risky conditions such as asthma.
Expect vaccination campaigns to start around Oct. 15 anyway, Hall said. They just will have to be smaller in scale than originally planned, as the supply trickles in more slowly.
"Why would we wait? As vaccine comes in, we'll ship it out to the states. We're not going to sit on it," Hall said.
The government had long insisted it was confident in the 120 million dose figure, even in late July as manufacturers from around the world revealed they were having serious problems brewing shots. The chief ingredient is grown in chicken eggs, and companies were getting 30 percent of usual doses per egg as they do with regular winter flu vaccine.
Health officials are working to address that problem by delivering to manufacturers virus strains expected to grow better.
A more recently discovered problem is a bottleneck in getting vaccine from huge vats into the syringes needed to deliver them, because of a limited number of those so-called finish-and-fill facilities, Hall said.
Another delay is in developing the test needed to make sure doses are at the proper strength before they're cleared for use.
The problem is with swine flu vaccine, not vaccine against the regular winter flu. Unlike its new cousin, regular flu is riskiest for older adults. Those inoculations already are beginning in parts of the country, and there is ample supply of seasonal vaccine.
As for the swine flu - also known as H1N1 flu, for its viral family - nearly 160 million people are in the groups to get priority for vaccination. But health officials don't expect nearly that much demand, especially since while swine flu can kill, for most people it appears to be a milder disease than regular flu. Traditionally, only about 40 percent of people recommended to get regular flu vaccine do so.
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