Federal health officials say the U.S. is without doubt in the middle of a second swine flu wave, with the virus more widespread than ever. Since its onset in April, the 2009 H1N1 virus has caused more than 1,000 deaths and more than 20,000 hospitalizations in this country, officials from the Centers For Disease Control And Prevention said Friday. Similarly, children's deaths from flu and pneumonia have been higher than what is normally expected at this time of year.
"This remains largely a young person's disease," CDC Director Thomas Frieden said.
Compared with seasonal flu, young people and children continue to be disproportionately affected by the virus. In the first 11 days of October, one in five kids had influenza-like illness — fever, cough, fatigue, aches and pains.
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Since April, there have been 95 confirmed pediatric 2009 H1N1 deaths, and nearly half of them have occurred during September and October, according to the CDC.
Across the country, dueling concerns persist: Some people worry that they won't have access to the vaccine, while others question the vaccine's safety.
The H1N1 vaccine has been available for nearly three weeks, but health officials haven't been able to deliver as many doses as expected. The CDC planned to have in hand 40 million doses by the end of October. But as of Friday, only 16.1 million doses were available to states, according to the CDC.
Part of the problem is that the yield is lower than expected; manufacturers are having more trouble coaxing the virus to grow than they've had with other vaccines.
Even as lines to get the vaccine are wrapping around the block in some places, many express high levels of distrust about the safety of the vaccine. According to a Harvard poll conducted in September, 33 percent of people think the H1N1 vaccine is safe, compared with 57 percent who trust the seasonal flu vaccine.
Frieden said there is every reason to be confident in the safety of the H1N1 vaccine, which is produced the same way as the seasonal flu vaccine. Millions of doses of seasonal flu vaccine are administered every year, he said, with an excellent safety track record. Also, health officials are not seeing any big changes in the genetic nature of the swine virus that would make it less susceptible to vaccine, he said.
CDC officials said they expect that the flu will continue in waves, but they ventured no predictions on how long the pandemic will last.
Percentage Of Health Visits for Flu-like Illness
Across the country about 4,000 providers and clinicians report data each week about how many patients they've seen for flu-like illness. In 2009, most flu cases are H1N1, according to the CDC.
There was no week 53 during the 2006-2007 or 2007-2008 influenza seasons. The week 53 data point for those seasons is an average of weeks 52 and 1.