A summary of presentations from the weekly Summit partner webinars
January 26, 2023 – The latest Summit Summary
Flu Surveillance Update – Alicia Budd (CDC)
Alicia Budd, MPH, Influenza Division, CDC, gave a Flu Surveillance Update through week two, ending January 14. (View slides.)
Virologic Surveillance
Virologic Surveillance – Percent Positive for Influenza
- Seeing a sharp decline in the percentage of specimens that tested positive for flu
- Seeing this for more than a month in all ten regions
- Vast majority of viruses are influenza A
- Small percentage of influenza B
Virologic Surveillance – Virus Characteristics
- H3 predominance
- 77% H3
- 23% H1
- As of October 2, 2022
- Almost all of H1 and all of H3 belong to the 5a.1 subclade
- All H3 belong to the 2a.2 subclade
- A bit more variability among B Victoria, with more than 90% in the 31.2 subclade
- All specimens tested are similar to cell-grown vaccine reference virus
- More than 1,300 specimens tested for flu antiviral agents with no antiviral resistance identified
Outpatient Respiratory Illness – people resenting to outpatient urgent care, primary practice, or emergency department for fever and cough or sore throat
- Numbers are continuing to drop
- Still slightly above the national baseline
- In regions 5 (midwest), 6 (south), and 8 (mountain), percent of visits dropped below the baseline
- Declines are reported in all age groups
Long-term Care Facilities (LTCF) and Hospitals
HHS Protect – Percent of LTCF that reported at least one influenza positive test among residents
- Decline for several weeks and declining sharply now
- Hospitalizations have significantly declined in last several weeks
FluSurv-NET – Age-specific information
- Cumulative rate of the season as a whole: This has been an early season, and there have been higher levels of activity every week than previously seen for the given week
- About to cross where U.S. was in the 2017–2018 season at this same time
- Close to leveling off, whereas the 2017–2018 was still climbing at this time
- This season may fall short of where a lot of seasons fall based off where numbers are now
- Second wave possible
- So far, sharp increase followed by sharp decrease
Mortality – Percent of deaths from pneumonia, influenza, and COVID-19 (PIC)
- First part of season saw an increase in PIC deaths attributed to flu
- Last 4–5 weeks, percentage of deaths due to flu has been declining
- Influenza-associated pediatric deaths
- 85 deaths this season so far
- Within the range of numbers of pediatric deaths reported for seasonal flu each year before the COVID-19 pandemic
Preliminary In-Season Flu Burden Estimates, 2022–2023
- 25–50 million illnesses
- 12–24 million medical visits
- 270–600 thousand hospitalizations
- 17–52 thousand deaths
Summary
- Flu activity is declining in most areas of the country
- H3N2 remains predominate virus
- Declining activity doesn’t mean no activity
- Surveillance continues year-round
- Is virus changing? (e.g., might we have a wave of influenza B or A/H1N1 later this season?)
- Is activity increasing again?
Questions
Q: The increase in PIC deaths may not be COVID-19- or flu-related. Are you seeing a difference in proportion that is not accounted for by COVID-19 or flu? Are there many more secondary bacterial infections causing pneumonia after other viral infections?
Alicia Budd: It is certainly going to be impacted by other viruses that we have been looking at. The proportion of death certificates coded for COVID-19 also have pneumonia and other various diagnoses listed, but there hasn’t been a drastic change in that. We are seeing increases in other respiratory viruses as well, so that could be part of the cause for pneumonia increasing, and the percentage of PIC deaths that have COVID-19 listed has been increasing sharply recently. I think that’s what’s driving some of it, but certainly, not all of it, as you mentioned.
Q: We are at 85 pediatric deaths reported now. Can you put that into context? What is the typical range?
Alicia Budd: The highest number we had was in the 2019-2020season, which was 199. We are below that at this point and falling within the range of prior years. There is quite a bit of variability from year to year. Season 2011–2012 was the lowest.
Q: Do you have a sense of what proportion of flu seasons one often sees a peak of one type or subtype and then a second later?
Alicia Budd: Excluding the COVID-19 seasons, it has been happening more frequently. We have been having these two waves quite often in recent years.
Announcements
- Immunize.org, with pain mitigation expert, Anna Taddio, PhD, will host a free, 1-hour webinar, Improving the Vaccination Experience: Reducing Pain and Anxiety for Children and Adults, on February 28 at 1:00 p.m. (ET). All are welcome to register!
- The dates for the NAIIS in person meeting will be May 9–11, so mark your calendar. Registration information to come.
- If you are registered for the Summit not getting the emails from Mailchimp, please add “NAIIS” at info@izsummitpartners.org to your contact list.
- If you have any agenda items that you are interested in sharing with the Summit, please let us know and we can add you to an upcoming call as a speaker or panelist. Contact information: info@izsummitpartners.org.
