TUESDAY, Nov. 3 (HealthDay News) -- The United States has 31.8 million H1N1 flu vaccine doses available and is on track to have another 10 million ready by week's end, a federal health official said Tuesday.

So far, that isn't enough to prevent long lines at vaccination centers, but it is consistent with what officials had projected earlier this week.

"We're having a steady increase in the availability of vaccine, but not nearly as rapidly as we would have liked," Dr. Thomas Frieden, director of the U.S. Centers for Disease Control and Prevention, told reporters during an afternoon teleconference. "That is encouraging, but it is not nearly as much as we would like. We realize it is frustrating and inconvenient [to patients and to physicians]. As public health professionals, it is frustrating because, in part, many people who seek the vaccine will not get vaccinated later. They might not come back. We ask people to continue to be persistent."

In response to a report that 6,000 flu shots had to be discarded in Pennsylvania because they weren't stored at the proper temperature, Freiden said, "We regret it when there's any loss of vaccine, but when you think that we now have 30 million doses out there, and we've only had a few examples of improper handling that led to the vaccines having to be discarded, this type of thing is virtually inevitable and we're glad it's been relatively rare."

Officials also reported that more health-care workers than usual are availing themselves of the seasonal flu vaccine.

"We're seeing a higher uptake of the seasonal influenza vaccine by health care workers than in previous years," said Frieden. "We'll have to wait and see how that goes and how extensive it is."

Demand for the regular, seasonal flu vaccine among the general population has also been unprecedented, Frieden added, with 90 million doses already distributed to providers and 114 million expected to be available through the market by year's end.

However, virtually all of the flu being diagnosed right now is H1N1.

"We're seeing almost no seasonal flu," Frieden said. That doesn't mean the seasonal flu shot won't be needed, however. "What the rest of the season holds, only time will tell," the CDC director said.

Frieden also reiterated the importance of antiviral medications, such as Tamiflu or Relenza, regardless of whether the vaccine is available. That's especially true for people with certain medical troubles, he said.

"For people with asthma and other underlying conditions, it's particularly important to get vaccinated when the vaccine becomes available," he said. "If you have fever and cough, get treated promptly. People with asthma account for about one-third of all people hospitalized with H1N1. We know that only half of people with asthma, when they get sick with flu, sought care from a medical provider. If you have asthma or other underlying conditions, seek care promptly."

As always for everyone, the message of the season is wash your hands frequently, cover your mouth when sneezing or coughing, and stay home if you are sick.

"The flu season lasts till May, and this flu season is unlike any other for at least 50 years," Frieden said. "We don't know what will happen, but we will continue to monitor and do everything we can to prevent or reduce the spread of flu."

More information

There's more on H1N1 influenza at the U.S. Centers for Disease Control and Prevention.

SOURCE: Nov. 3, 2009, teleconference with Thomas R. Frieden, M.D., director, U.S. Centers for Disease Control and Prevention, Atlanta

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