|
National Influenza Activity:
• According to this week’s FluView report, influenza activity is increasing slightly among children, but remains low nationally.
• CDC continues to provide updated information and materials on the current HPAI A(H5N1) situation. The webpage can be viewed here.
In the News
MMWR Report
Influenza, COVID-19, and Respiratory Syncytial Virus Vaccination Coverage Among Adults — United States, Fall 2024 | MMWR
Preliminary Estimates for 2024-2025 Flu Season Burden and Severity:
2023-2024 Flu Season Summary:
A press release describing the first reported infection in a child in the United States: CDC confirms H5N1 Bird Flu Infection in a Child in California | CDC Newsroom
National Influenza Vaccination Week (NIVW) is December 2–6. It is a critical opportunity to remind everyone 6 months and older that there's still time to protect themselves and their loved ones from flu this flu season by getting their annual flu vaccine if they have not already. CDC data shows that flu vaccination coverage was lower last season, especially among certain higher risk groups, including children. When you get a flu vaccine, you reduce your risk of illness, and flu-related hospitalization if you do get sick. This week is meant to remind people that there is still time to benefit from the first and most important action in preventing flu illness and potentially serious flu complications: get a flu vaccine today. Check out CDC's NIVW toolkit for more shareable resources and content.
Influenza Activity in the U.S.
Key Points:
• Nationally, percent positivity for influenza overall increased this week and the percentage of emergency department visits for influenza increased slightly among pediatric age groups.
• During Week 46, of the 309 viruses reported by public health laboratories, 293 were influenza A and 16 were influenza B. Of the 211 influenza A viruses subtyped during Week 46, 77 (36.5%) were influenza A(H1N1)pdm09, 129 (61.1%) were A(H3N2), and 5 (2.4%) were A(H5).
• Six confirmed human infections with influenza A(H5) viruses were reported to CDC this week. To date, human-to-human transmission of influenza A(H5) virus has not been identified in the United States.
• CDC recommends that everyone ages 6 months and older get an annual influenza (flu) vaccine.
•There are prescription flu antiviral drugs that can treat flu illness; those should be started as early as possible and are especially important for higher risk patients.
• Influenza viruses are among several viruses contributing to respiratory disease activity. CDC is providing updated, integrated information about COVID-19, flu, and respiratory syncytial virus (RSV) activity on a weekly basis.
Below is a summary of the key influenza indicators for the week ending November 16, 2024:
Viral Surveillance - Clinical Lab: The percentage of respiratory specimens testing positive for influenza at clinical laboratories is 2.1% this week.
Viral Surveillance - Public Health Lab: Influenza A(H1N1)pdm09 and A(H3N2) were co-circulating this week.
Virus Characterization: Influenza virus characterization information can be found here: U.S. Influenza Surveillance: Purpose and Methods | CDC
Outpatient Illness: The percentage of patient visits to a health care provider for respiratory illness in week 46 was 2.7% which is below baseline.
Outpatient Respiratory Illness: ILINet Activity Map: Three jurisdictions experienced moderate ILI activity but no jurisdictions experienced high or very high ILI activity in week 45.
Laboratory-Confirmed influenza Hospitalizations can be found here: Laboratory-Confirmed Influenza Hospitalizations (cdc.gov) The weekly hospitalization rate observed in Week 46 was 0.3 per 100,000 population. The cumulative hospitalization rate was 1.2 per 100,000 population.
NCHS Mortality: 0.03% of deaths were due to influenza. This percentage remained stable (< 0.1 percentage point change) compared to week 45. (NCHS:National Center for Health Statistics)
Influenza-Associated Pediatric Deaths: One influenza-associated death was reported this week. Two pediatric deaths have been reported so far this season. For more information: https://gis.cdc.gov/GRASP/Fluview/PedFluDeath.html
CDC FluView Site
https://www.cdc.gov/fluview/
Influenza Activity in Massachusetts
For more information about flu, please go to our Viral Respiratory Disease Dashboard which includes information not only on influenza but also other acute respiratory diseases, COVID-19, and respiratory syncytial virus (RSV), wastewater data and immunizations for respiratory diseases.
The figure below shows that for MMWR week 46, the percent of ILI visits in the current week is slightly below the regional baseline of 1.9%. (The CDC uses trends from past years to determine a region-specific baseline rate of ILI visits, which for Massachusetts is 1.9%. A rate above this regional baseline indicates higher than normal levels of ILI in the state.) For more information on how regional baselines are calculated see CDC’s influenza surveillance website at U.S. Influenza Surveillance: Purpose and Methods | FluView | CDC) For more information on weekly flu activity, see CDC’s influenza surveillance website at https://www.cdc.gov/fluview/surveillance/index.html.
| 
