CDC: Seasonal Influenza Activity Continues to Increase in the US

Different influenza strains continue to cocirculate in the United States as seasonal flu activity continues to increase.

The proportion of outpatient visits for influenza-like illness (ILI) increased to 5.1%, in the week ending February 16, 2019, which is above the national baseline of 2.2%, according to the CDC’s Feb. 22 FluView update. High ILI activity was reported in 30 states and in New York City.

The cumulative rate for influenza-associated hospitalizations, confirmed with laboratory testing, for the week was 27.4 per 100,000 population. The highest hospitalization rate (75.6) was among adults age 65 years and older.

The proportion of deaths attributed to pneumonia and influenza was below the system-specific epidemic threshold in the National Center for Health Statistics Mortality Surveillance System. However, 7 more children were reported to have died from influenza-associated illness, according to the update. These deaths are among 41 pediatric patients with influenza viruses that were reported to have died during the 2018-2019 flu season, through Feb. 16.

In the week ending Feb. 16, the percentage of respiratory specimens testing positive for influenza viruses in clinical laboratories increased. In addition, influenza was reported as widespread in 48 states and in Puerto Rico.

During the most recent 3 weeks, influenza A (H3N2 ) viruses were reported more frequently in some regions, but influenza A (H1N1)pdm09 viruses were predominating in most areas of the country.

Reference

CDC. Influenza (flu): influenza season week 7 ending February 16, 2019. CDC's FluView. https://www.cdc.gov/flu/weekly/. Updated February 8, 2019. Accessed February 8, 2019.