National Influenza Activity:
According to this week’s FluView report, key indicators that track flu activity remain high, but indicators that track severity (hospitalizations and deaths) are not high at this point in the season.
Below is a summary of the key influenza indicators for the week ending January 4th:
Viral Surveillance - Clinical Lab: The percentage of respiratory specimens testing positive for influenza at clinical laboratories decreased from 26.4% last week to 23.3% this week.
Viral Surveillance - Public Health Lab: Nationally, B/Victoria viruses are most common followed by A(H1N1)pdm09 viruses. The predominant virus varies by region and age group. There is low circulation of A(H3N2) and B/Yamagata viruses.
Virus Characterization and Antiviral Resistance: Genetic and antigenic characterization and antiviral susceptibility of influenza viruses collected in the U.S. this season is summarized in the CDC FluView report.
Outpatient Illness - ILI Net: Visits to health care providers for influenza-like illness (ILI) decreased from 7.0% last week to 5.8% this week. All regions remain above their baselines.
Outpatient Illness- ILINet Activity Map: The number of jurisdictions experiencing high ILI activity increased to 37 this week compared to 28 last week.
Geographic Spread of Influenza: The number of jurisdictions reporting regional or widespread influenza activity increased to 50 this week compared to 48 last week.
Influenza-associated Hospitalizations: The overall hospitalization rate for the season increased to 14.6 per 100,000. This is similar to what has been seen at this time during recent seasons.
Pneumonia and Influenza Mortality: The percentage of deaths attributed to pneumonia and influenza is 5.8% which is below the epidemic threshold.
Influenza-associated Pediatric Deaths: Five new influenza-associated pediatric deaths occurring during the 2019-2020 season were reported this week. The total for the season is 32.