TUESDAY, Oct. 27, 2009 (HealthDay News) -- The H1N1 swine flu is spreading throughout the United States and vaccine remains in short supply, but federal health officials said Tuesday that more than 22 million doses are now available, with more expected in coming weeks.
"This is a challenging time," Dr. Thomas R. Frieden, director of the U.S. Centers for Disease Control and Prevention, said during a press conference Tuesday. "We wish we had more vaccine available."
Frieden noted that they had anticipated having significantly more vaccine available by now, but "we are beginning to see significant increases in vaccine production, vaccine distribution and we do think it will get easier to find vaccine in the weeks that come," he said.
As of today, there are a total of 22.4 million doses available, an increase of 8 million doses since last week, Frieden said.
He would not say how much vaccine would be available by month's end. Earlier this year, the CDC said it expected to have as many as 40 million doses available by the end of October, but the agency later downsized that estimate to between 28 million and 30 million doses. At Tuesday's press conference, Frieden would only say that, "by Friday we will let you know what was achieved by Friday."
According to the CDC, H1N1 flu is now widespread in 46 states, with more than 1,000 related deaths reported since the strain emerged in April.
The H1N1 vaccine that is now available comes in the form of either a nasal mist or a standard injection. The first doses to reach high-risk Americans came only in the nasal spray form, called FluMist, designed for healthy people between 2 and 49 years of age. Now, more than half the doses are injectable, Frieden said.
The current H1N1 vaccine is being produced by the traditional method of growing the virus in eggs. And although the method is safe and used for most flu vaccine production, it is slow.
Had there been H1N1 vaccine available earlier it would have been incorporated as part of this year's seasonal flu shot, Frieden said.
"If we had H1N1 earlier in the season we would have most likely included it in the seasonal flu vaccine. So it would have been part of the regular flu vaccination program, as it will be for the Southern Hemisphere in [their] coming flu season," he said.
"We wish we had better technology," Frieden said. "We wish we had a technology that could produce vaccine in weeks or months rather than the six to nine months that it takes given the current tried-and-true technology," he said.
Other vaccine technologies are available, including cell-based vaccine and DNA technologies, Frieden noted. "They are all still experimental. We are not using any of them in this," he told reporters.
There is some encouraging news, Frieden said. The genetic makeup of the H1N1 virus hasn't changed since it first surfaced in April, meaning the swine flu vaccine and the antiviral drug Tamiflu are a good match.
In addition, there have been no changes in who appears most at risk for the swine flu, including children and young adults, he said.
While children continue to be particularly vulnerable to the disease, Frieden said Friday, "we are seeing it increasingly affect young adults as well as children. We are still not seeing significant numbers of cases among the elderly, and that's characteristic of this virus."
That's a marked difference from run-of-the-mill seasonal flu, which typically poses a much bigger threat to the elderly.
Last Friday, Frieden said the H1N1 flu would probably occur in waves, but "we can't predict how high, how far or long the wave will go, or when the next will come," he added.
"We are now in the second wave of pandemic influenza and whether this will continue through the fall into the winter, whether it will go away and come back in traditional flu season, only time will tell," he said.
For more information on H1N1 swine flu, visit the U.S. Centers for Disease Control and Prevention.