ATLANTA, Jan. 20 (UPI) -- U.S. health officials say they used community-based surveillance -- telephone inquiries -- to track influenza-like illness during the 2009-2010 flu season.
Thursday's Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report said most influenza surveillance is done in hospitals or doctor's offices, where cases can be tracked and some are confirmed through testing, but this study monitored influenza-like illness by calling people at home and asking them questions about their symptoms.
"Community-based surveillance of influenza-like illness described in this report provided the only source of information regarding persons with influenza-like illness who did not seek care during the 2009-10 influenza season," the report said. "Results indicate that influenza-like illness reports were widespread during the 2009-2010 influenza season, with a substantial percentage seeking care for their symptoms."
Influenza-like illness peaked in October and November 2009 and was more common among younger respondents and American Indian adults and children, the report said.
Health officials at the CDC said they are continuing to use the influenza-like illness questioning during the 2010–2011 influenza season to better understand year-to-year trends and factors associated with reported influenza-like illness.
