Demand Outpacing Supply of H1N1, Seasonal Flu Vaccines

The overwhelming majority of Americans who have tried to get vaccinated against the novel influenza A (H1N1) virus have been unable to do so, according to a recent poll from the Harvard University School of Public Health, Boston.

Meanwhile, the CDC said on Nov. 9 that nearly 80 percent of seasonal flu vaccine already has been distributed to vaccine providers, and a surge in uptake may leave supplies short of demand.

Researchers at the Harvard School of Public Health polled 1,073 individuals ages 18 and older from Oct. 30-Nov. 1. Of that total, 17 percent said they have tried to get the H1N1 vaccine for themselves. In addition, of the 282 respondents who identified themselves as parents, 41 percent said they have tried to get the H1N1 vaccine for their children.

However, only 30 percent of adults who tried to get the vaccine for themselves succeeded in doing so, the researchers found, and only 34 percent of parents who sought vaccine for their children were successful.

According to the survey results, 21 percent of those polled said they had been diagnosed with a chronic condition or were immunocompromised, 8 percent said they were health care workers or emergency response personnel, and 3 percent said they lived in a household or provided care for a child younger then age 6 months. Three percent of females polled reported they were pregnant.

The CDC has estimated that more than 40 million Americans fall into the priority groups recommended to receive H1N1 vaccine before others while supplies remain limited. Those groups are

Overall, the researchers reported, 21 percent of high-priority individuals said they tried to get the H1N1 vaccine, but only 34 percent of those who tried were able to do so.

In addition, nearly half of the Harvard poll's respondents indicated they were unable to find information about the location of available H1N1 vaccine in their area.

"I think it's not surprising that many people didn't know where to get vaccine," said Anne Schuchat, M.D., director of the CDC’s National Center for Immunization and Respiratory Diseases, during a Nov. 6 media briefing that coincided with the release of the poll results. "I think (that for) the first few weeks of the program, vaccine has been in very limited supply."

Schuchat pointed out that there was some encouraging news in the Harvard poll: More than 90 percent of those who had tried but failed to get vaccinated said they would try again to get the vaccine for themselves, their children or both.

According to the CDC's H1N1 vaccine supply status page, more than 47 million doses of H1N1 vaccine had been produced and allocated to project areas nationwide as of Nov. 16.

Meanwhile, CDC Director Thomas Frieden, M.D., said during a Nov. 3 media briefing that there is "unprecedented demand" for seasonal flu vaccine, and about 90 million doses -- or roughly 79 percent of the volume expected this season -- already had been distributed to providers.

"We continue to hear that people are unable to get the vaccine," Frieden said. "We think this year will be the highest ever uptake on seasonal flu vaccine. We anticipate there being around114 million doses of seasonal flu vaccine available through the market by the end of the year. It may be there is even greater demand than that by the end of the season."

Vaccine for the 2009-2010 influenza season was made available earlier than normal to make way for H1N1 immunizations. The CDC said on Nov. 9 that the early availability of the seasonal flu vaccine, combined with increased interest in vaccination, has led to increased uptake.

According to the CDC, sanofi pasteur, the nation's largest supplier of seasonal flu vaccine, is experiencing delays in shipping. The agency said physicians seeking additional seasonal vaccine may be unable to purchase it and may have to obtain vaccine from a source other than their usual supplier.

The agency directed physicians seeking information about seasonal vaccine supply to the Influenza Vaccine Availability Tracking System sponsored by the National Influenza Vaccine Summit's Prevent Influenza Now! initiative, where information is available about wholesale distributors and manufacturers with vaccine in stock.

CDC officials have said there has been little seasonal flu activity reported to date, and H1N1 flu accounts for the vast majority of circulating flu in the country. Schuchat noted during the Nov. 6 CDC briefing that there is still time to be immunized with seasonal flu vaccine.

"Usually, seasonal flu strains don't increase until December through May," she said. "Now everything we are seeing is the H1N1 virus. Hopefully, there will be additional (seasonal flu vaccine) supplies. They may not be ample to reach the tremendous demand that we are seeing this year."