A new snag in production of swine flu vaccine has the government hunting for more companies that can package it.

The man in charge of vaccine procurement at the Department of Health and Human Services says if there are early outbreaks in September and October, there could be increased demand for the shots.

"We're trying to bring on more manufacturing" for the packaging step that has emerged as a logjam, said Dr. Robin Robinson, the Department of Health and Human Services official in charge of vaccine procurement. "Hopefully, there are ways to bring that number up."

Health and Human Services expected to have 120 million doses of the vaccine by Oct. 15. But it now thinks it will fall far short of that — only 45 million — although that's expected to rise to 85 million doses by the end of October.

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The full 195 million the government has ordered is expected by December, the long-set date for final delivery.

The U.S. hardly ever administers that much regular flu vaccine so early in the season, and the change will not delay plans to go ahead and start swine flu inoculations, Robinson said.

But he acknowledged that if there are early outbreaks in September and October, there could be increased demand for the swine flu vaccine.

"As we've all along said, if things can go wrong they will," Robinson said.

Manufacturers around the world disclosed in July that they were having serious problems brewing shots. The chief ingredient is grown in eggs, and companies were getting far fewer doses per egg than they usually do for regular winter flu vaccine.

Health authorities have delivered new "seed strains" of the virus to manufacturers to help with that problem, Robinson said.

But in addition to the packaging logjam, other factors are adding to the delay, including:

—One manufacturer, France-based Sanofi-Pasteur, took longer than expected to finish brewing the regular winter flu vaccine, delaying the swine flu work, Robinson said. "We knew there were problems," but only recently the extent, he said.

—Another supplier, Australia's CSL, recently notified the U.S. that its shipments will arrive later than promised because it first must provide batches to its home country, where the flu season is winding down. Although the U.S. signed a contract with CSL first, "there was always the possibility they could do that," Robinson said. "Our laws can do the same thing. We don't, but we could."

—And it took health authorities longer than anticipated to develop the tests, called reagents, required to ensure doses are at the proper strength before they are cleared for use.