Weekly U.S. Influenza Surveillance Report | Seasonal Influenza (Flu) | CDC

Weekly U.S. Influenza Surveillance Report | Seasonal Influenza (Flu) | CDC

The most recent FluView report shows that flu activity continues to decrease in the United States, but remains slightly elevated. While flu activity has peaked nationally for this season, some parts of the country are still experiencing widespread flu. Ongoing activity is expected to continue for a number of weeks. Also, flu viruses circulate at low levels during the summer.

CDC recommends a yearly flu vaccine for everyone 6 months and older. Vaccination can reduce flu illnesses, doctors' visits, and missed work and school due to flu illness, as well as prevent flu-related hospitalizations.

CDC also recommends that patients suspected of having influenza who are athigh risk of flu complications or who are very sick with flu-like illness should receive prompt treatment with influenza antiviral drugs without waiting for confirmatory testing.

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All data are preliminary and may change as more reports are received.

Synopsis:

During week 17 (April 24-30, 2016), influenza activity decreased in the United States.

• Viral Surveillance: The most frequently identified influenza virus type reported by public health laboratories during week 17 was influenza B. The percentage of respiratory specimens testing positive for influenza in clinical laboratories decreased.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below their system-specific epidemic threshold in both the NCHS Mortality Surveillance System and the 122 Cities Mortality Reporting System.
• Influenza-associated Pediatric Deaths: Four influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A cumulative rate for the season of 30.6 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 1.8%, which is below the national baseline of 2.1%. Three of 10 regions reported ILI at or above region-specific baseline levels. Puerto Rico and two states experienced moderate ILI activity; three states experienced low ILI activity; New York City and 45 states experienced minimal ILI activity; and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in Guam, Puerto Rico, and 7 states was reported as widespread; 15 states reported regional activity; the District of Columbia and 17 states reported local activity; and the U.S. Virgin Islands and 11 states reported sporadic activity.