A summary of presentations from the weekly Summit partner webinars
February 3, 2022 – The latest Summit summary
Flu Surveillance Update – Alicia Budd (CDC)
Influenza Virologic Surveillance – U.S., 10/3/21–1/22/22:
After a few weeks of decline in flu activity, the percent positive in week three is at 2%. Most of the HHS regions are seeing the same pattern with only a couple of regions having a slight increase in percent positive between week two and three. Even with the decline, it’s not possible to say the flu season is over yet.
Public health laboratories are reporting that nearly all of the viruses circulating in the U.S. are Influenza A(H3N2). All of the H3N2 viruses belong to the 3C.2a1b clade and the 2a.2 subclade. There are very few Influenza A(H1) and Influenza B (Victoria) viruses.
Of almost 500 specimens tested so far, there has been no antiviral resistance or reduction in susceptibility identified for the four antiviral agents used for flu
Outpatient Visits for Respiratory Illness, Reported by the U.S. Outpatient Influenza-like Illness Surveillance Network (ILINet): Influenza-like illness (ILI) refers to someone who has a fever and cough or sore throat and could be caused from a number of respiratory viruses, including flu and COVID-19. The percentage in ILI has been declining, with week three being the third week of decline, with network providers specifying that 2.8% (national baseline 2.5%) of visits are ILI-related. This decline was seen in all HHS regions across all age groups. The decrease may have something to do with the decline in COVID-19 activity, as well.
ILI Activity Level, Determined by Data Reported to ILINet, Week ending January 22, 2022 (Week 3):
During week three, there were 12 jurisdictions reporting high levels of activity, compared to 21 two weeks ago (week one).
Percent of Long-Term Care Facilities (LTCF) with at least One Confirmed Influenza Case among Residents, Reported to CDC’s National Healthcare Safety Network (NHSN), National Summary, 10/4/21–1/23/22:
The number of LTCF reporting at least one flu positive case has declined from the previous week.
Influenza hospitalizations in the U.S.:
HHS Protect shows that this week there were just under 1,000 flu hospitalizations. Week three was the third consecutive week of decline in the number of flu positive admissions.
Cumulative influenza associated hospitalization rate from FluServNet shows a 4.3 hospitalizations/100,000 population. This is a lower rate compared to the last four seasons immediately prior to COVID-19, but slightly higher than the 2016–16 season at this same point.
Influenza-related mortality data, U.S.:
As of January 27, the percentage of death certificates that list pneumonia, influenza, or COVID-19 (PIC) as the cause of death continued to increase in week three up to 28.4%. This is being driven almost entirely by COVID-19 and not the flu. Of the almost 6,000 PIC deaths reported in week three, more than 5,000 listed COVID-19 as cause of death and only 27 listed flu.
There have now been five pediatric deaths this season, all of which were infected with an Influenza A virus.
2021–22 U.S. Flu Season: Preliminary In-Season Burden Estimates
CDC is now posting preliminary in-season flu burden estimates, which are being updated weekly.
Estimates from October 1, 2021, to January 22, 2022:
- 2,000,000–3,400,000 flu illnesses
- 950,000–1,500,000 flu medical visits
- 20,000–41,000 flu hospitalizations
- 1,200–3,500 flu deaths
Estimated range of annual burden of flu in the U.S. from 2010–2020
- 9,000,000–41,000,000 flu illnesses
- 140,000–710,000 flu hospitalizations
- 12,000–52,000 flu deaths
International Influenza Activity, Number of Influenza Positives Reported to WHO’s FluNet, 10/2018–1/8/22:
Flu positive activity reported to the WHO is lower at this point in the season than would have been expected pre-COVID-19. There are declines in activity across the northern hemisphere. The southern hemisphere has declining activity, however, it is not as common to see flu activity in the southern hemisphere at this time. Globally, Influenza A(H3) viruses are dominant, with the exception of China reporting Influenza B (Victoria) as the dominant virus.
Flu surveillance shows that activity, including ILI illness, has held at the same levels, or decreased slightly, in the past few weeks. Although activity is hard to predict, flu is expected to continue at least for several more weeks. The majority of the viruses are influenza A(H3N2), which is genetically closely related to the vaccine virus with some antigenic differences. There has not been antiviral resistance identified. Preliminary in-season influenza burden estimates are now being updated and posted weekly.
CDC continues to recommend flu vaccination as long as flu activity continues.
Other Respiratory Virus Activity
- COVID Data Tracker Weekly Review
- COVID Data Tracker
- National Respiratory Virus Surveillance System (NREVSS)
How much should we take historical data into account this year since we don’t have any prior experience with the current situation, e.g., mitigation efforts to prevent COVID-19 transmission, reduced travel, etc.?
We may end up seeing historical data as a relevant baseline again at some point; however we are not there right now. We most likely are not done with flu season and may have another increase in activity. We are seeing off-season activity in the southern hemisphere, so flu activity is still being seen in other places. We can’t put too much stock into our usual peak in February, thinking we are out of the danger zone when we may not be there yet. Influenza is even less predictable this year than in a typical year.
Are there any predictions for flu activity for the upcoming season (2022–2023)?
It’s hard to even predict what will happen next week with the flu season. Hopefully we are watching COVID-19 transition from being a pandemic virus to being endemic, which is what may impact flu activity in the long term. There is so much that we don’t know, so it’s impossible to predict what flu will be like the next season.
Is CDC continuing to recommend flu vaccination during February?
If there is flu activity in a community, there’s value in giving the vaccine. The decision may be best made on a local level, as some communities have higher rates of circulation than others. Another thing to keep in mind is that because we see low activity now doesn’t mean this is where we will stay. If there is still flu activity, CDC will continue to recommend getting the vaccine.
Do you think there will be a universal vaccination requirement for healthcare workers?
David Kim: Given the history with mandates for the flu vaccine at the state level, I think it’s going to be dependent on the individual healthcare systems to make the decision.
Carolyn Bridges: When the first mandates were initiated by hospitals for their work forces, we saw an increase in flu vaccine uptake. In addition, when CMS required reporting of flu vaccination levels of healthcare workers, we saw increases in rates. Reporting had a substantial impact on flu vaccination uptake rates.
L.J Tan: The 2013 NVAC report recommended that healthcare facilities with healthcare worker flu vaccine uptake rates lower than 90% consider a form of influenza vaccination as a condition of employment requirement.
Are there any studies that will be looking at the impact of influenza vaccine on COVID-19 infection rates and/or outcomes?
Influenza vaccination does not prevent COVID-19 infection but can prevent co-infection of influenza with COVID-19, which can lead to more serious outcomes. Preventing the co-infection can improve COVID-19 outcome.
1. The NAIIS Annual meeting will be split into two segments The NAIIS Flu Day will be virtual this year. The tentative day for the virtual flu session is May 19 from 2:00–4:30 p.m. (ET). The adult vaccination component will hopefully be in person, COVID-19 permitting, in September or October, 2022.
2. Immunize.org has introduced a new patient handout to assist providers with influenza vaccination uptake: Not Sure If You Can Get an Influenza Vaccine?This handout, ideally printed as a two-sided, single page, addresses a variety of concerns (e.g., egg allergy, history of Guillain-Barre syndrome, pregnancy, and a weakened immune system). Immunize.org has also recently introduced How to Administer Multiple Intramuscular Vaccines to Adults During One Visit co-administration handout for healthcare workers.
3. We would welcome having even more NAIIS member organizations to add their support to the Call to Action on adult immunization. Access the call to actionand click on the top righthand button to add your organization.
4. If you are not getting NAIIS emails, please add email@example.com (sender: NAIIS) to your list of email contacts to keep receiving the NAIIS emails.
5. There is new zoom login information this year. Please check your emails with the call agendas from NAIIS for the new zoom link and password information.
6. Immunize.org hosted two influenza webinars in September that can now be viewed online.
- The Continued Threat of Influenza and How to Sustain Influenza Vaccination Efforts
- Translating COVID-19 Strategies to Improve Influenza Seasonal Flu Vaccination Efforts
7. Immunize.org, with funding support from CDC and Seqirus, is offering a limited quantity of FREE Flu vaccine and COVID-19 vaccine buttons and stickers. To receive these supplies at no cost, please order now: