THURSDAY, Dec. 8 (HealthDay News) — U.S. influenza incidence has been low for the first part of the season, the CDC announced recently in Morbidity & Mortality Weekly Report.
Lynnette Brammer, MPH, of the CDC in Atlanta, and colleagues collected data on 24,027 respiratory specimens from collaborating U.S. laboratories to provide a summary and update of U.S. influenza activity since Oct. 2, 2011.
The researchers found 266 specimens (1.1%) positive for influenza, of which 191 (71.8%) were influenza A and 75 (28.2%) were influenza B. The vast majority of influenza A viruses were H3 viruses — 90.8%. Thirty states in the 10 U.S. Department of Health and Human Services regions reported influenza virus, with most reports originating in the southeastern states.
“During Oct. 2 to Nov. 26, 2011, influenza activity remained low in the United States. Thus far, influenza A viruses have predominated, and the majority are antigenically related to the 2011-2012 influenza vaccine strains for the Northern Hemisphere,” the researchers wrote.