Sep 11, 2009 (CIDRAP News) –The United States is seeing increased levels of pandemic H1N1 influenza activity, with cases being reported in all 50 states and widespread activity in Guam and 11 states, most of them in the Southeast, the Centers for Disease Control and Prevention said today.
In last week's surveillance report, six states and Puerto Rico reported widespread activity, so the number of states reporting the highest activity has increased by five.
Anne Schuchat, MD, director of the CDC's National Center for Immunization and Respiratory Diseases, told reporters at a press conference that the level of outpatient visits for flu-like illness, 3.6%, is much greater than is normally seen in September and is as high as last winter's peak. She said most of the cases were in children and young adults, which is consistent with the pattern seen during the first months of the novel H1N1 outbreak.
Despite the uptick in flu activity, the CDC is seeing few school dismissals, Schuchat said. Only four school closures were reported this week, one of which was a small school that serves students with special needs.
So far the CDC has received reports of only a few oseltamivir-resistant pandemic H1N1 cases, she noted. "It's just a handful but something we're keeping our eye on." On the basis of samples tested, about 98% of circulating flu viruses are the novel flu strain.
The CDC said in its surveillance update today that it will wrap up the 2008-2009 flu season on Oct4. The latest report, for the week ending Sep 5, reflects a change in the way the CDC monitors and reports influenza-related hospitalizations and deaths. States can now report either lab-confirmed or pneumonia and influenza syndromic hospitalizations and deaths for all flu types and subtypes, not just pandemicH1N1. Counts were reset to zero on Aug 30. The number of hospitalizations since then reported by 29 states totals 1,380, and there were 196 deaths.
Health officials are expecting 115 million doses of seasonal flu vaccine this year, and about 38million of them should already be in providers' offices, Schuchat said. Earlier this week during a National Influenza Vaccine Summit conference call, officials said prebooking problems had led to some seasonal vaccine shortage reports. "We know as the season unfolds there may not be enough absolutely everywhere you're looking for it," she said.
"Seasonal flu typically will last all the way through May, and we think it's fine to get the vaccine now and take advantage of availability," she said. "The strain that's here is mainly [pandemic] H1N1, but we're expecting seasonal strains."
CDC weekly flu surveillance report