By Matt Binnicker, Ph.D.
Director of the Mayo Clinic Clinical Virology Laboratory
Associate Professor, Mayo Clinic College of Medicine
According to the Centers for Disease Control and Prevention (CDC), influenza activity increased in the United States during the week ending December 27, 2014.
- Nationwide, 30.4% (7,289 of 24,001) of specimens tested by reporting laboratories were positive for influenza.
- Widespread influenza activity was reported in 43 states, including Minnesota, Iowa, Wisconsin, and South Dakota. This represents an increase in the number of states experiencing widespread activity from 36 states reported the previous week.
- Influenza A (H3N2) viruses continue to be the most common subtype responsible for influenza-like illness this season.
- The highest rate of hospitalization was among adults aged ≥ 65 years followed by children aged 0 to 4 years old.
- A majority (68.3%) of the strains characterized at the CDC have shown some genetic drift from the strain included in the 2014–2015 influenza vaccine.
- To date, no resistance to commonly used antivirals (e.g., TamiFlu) used to treat influenza has been identified.
MicrobeWatch: Influenza A Testing at Mayo Clinic in Rochester (Jan. 5)
Influenza-Like Illness Activity Level (Jan. 5)
Source: CDC FluView
Geographic Spread of Influenza as Assessed by State and Territorial Epidemiologists (Jan. 5)
Geographic Spread of Influenza for Mayo Clinic Health System States (Jan. 5)