Flu season in full swing: CDC

According to the Centers for Disease Control and Prevention (CDC) Flu View website, the United States is having an early influenza season with most of the country now experiencing high levels of influenza-like-illness (ILI). The CDC defines ILI as fever (temperature of 100°F [37.8°C] or greater) and cough and/or sore throat.

From December 30, 2012 to January 5, 2013, the proportion of people seeing their health care providers for ILI decreased from 6.0% to 4.3% but remained above the national baseline for the fifth consecutive week. Also during this time period, 24 states and New York City reported high ILI activity.

Forty-seven states reported widespread geographic influenza activity. This was an increase from 41 states in the previous week.

Influenza-associated hospitalizations were highest among people 65 and older. Of the 3710 influenza-associated hospitalizations that have been reported this season (as of January 5), 46% have been among people 65 and older. Nearly 20% (18.2%) of adults who were hospitalized for influenza were pregnant. (These patients may have had other underlying conditions as well.)

During the week ending January 5, 2013, 3369 of the 4222 influenza-positive tests reported to the CDC were influenza A and 853 were influenza B viruses. Of the 1586 influenza A viruses that were subtyped, 98% were H3 viruses and 2% were 2009 H1N1 viruses.