Situation Update: Summary of Weekly FluView
FluView - Weekly Influenza Surveillance Report
Update: Influenza Activity — United States, September 28, 2014–February 21, 2015. MMWR March 6, 2015 / 64(08);206-212
Why CDC Recommends Influenza Antiviral Drugs
CDC Presents Updated Estimates of Flu Vaccine Effectiveness for the 2014-2015 Season
Flu activity is still elevated in the United States but is declining. It is possible, however, that flu activity will continue for several weeks in parts of the country.
While H3N2 viruses remain most common, an increase in influenza B viruses has been detected in some parts of the country. This season has been severe for people 65 years and older, with very high hospitalization rates being recorded.
Influenza antiviral drugs can treat flu illness. CDC recommends these drugs be used to treat people who are very sick or who are at high risk of serious flu-related complications who have flu symptoms. Early antiviral treatment works best.
During week 8 (February 22-28, 2015), influenza activity continued to decrease, but remained elevated in the United States.
- Viral Surveillance: Of 16,821 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 8, 1,834 (10.9%) were positive for influenza.
- Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was at the epidemic threshold.
- Influenza-associated Pediatric Deaths: Six influenza-associated pediatric deaths were reported, including one influenza-associated pediatric death that occurred during the 2013-2014 season.
- Influenza-associated Hospitalizations: A cumulative rate for the season of 53.5 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
- Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 2.5%, above the national baseline of 2.0%. Seven regions reported ILI at or above region-specific baseline levels. Puerto Rico and six states experienced high ILI activity; four states experienced moderate ILI activity; 10 states experienced low ILI activity; New York City and 30 states experienced minimal ILI activity; and the District of Columbia had insufficient data.
- Geographic Spread of Influenza: The geographic spread of influenza in Guam and 12 states was reported as widespread; Puerto Rico, the U.S. Virgin Islands, and 30 states reported regional activity; the District of Columbia and six states reported local activity; and two states reported sporadic activity.