After a Rare Mild 2020-2021 Season, Influenza Is Back

During the week ending July 16, 2022, some 400 to 2400 new hospital admissions of patients with influenza likely will be confirmed and reported throughout the United States.¹ In comparison, rates of influenza infection were nearly negligible during the 2020-2021 season.² This, perhaps, is not surprising, since there was a partial shutdown of the United States and many COVID-19 countermeasures were in place over that period. Disease spread likely was mitigated by even stronger countermeasures in Southeast Asia, where influenza’s annual migration to the Americas may begin.³ Travel was suppressed, and vaccination rates for influenza among adults were the highest ever recorded, cresting 50% for the first time.⁴

During that 2020-2021 season, pharmacies surpassed doctors’ offices to become the most frequent sites of care for adult influenza vaccine administration, and pharmacy staff delivered more than one-third (39%) of all adult vaccines.^5-7 The 2021-2022 season has been associated with far fewer rates of infection and hospitalization than noted during prior seasons, yet influenza infection rates remain high; pharmacists need to remain vigilant throughout these summer months.^1,8,9

High Hospitalization Rates Linger

This 2021-2022 season has produced a substantial, though lower than average, rate of hospitalizations.^8,9 Data from the CDC indicate a typical rise in hospitalizations over the winter holidays, followed by a drop in hospital admissions, a steady gain starting in the beginning of February, a peak in early May, and a rate of hospitalizations that has remained above 2000 cases per week ever since (Figure 1).¹ We are not out of the woods this season; rather, Americans are being hospitalized for influenza at rates similar to those seen over the winter holidays. Interestingly, this spring’s rise in hospitalization rates coincides with reduced COVID-19 countermeasures and a broader “opening up” of the country.

Late Influenza Season Causes An Extension of Surveillance Into the Summer

The Influenza Hospitalization Surveillance Network (FluSurv-NET) consortium provides flu-based surveillance for the CDC. Owing to the late-season rise in influenza cases and hospitalizations, the consortium’s monitoring has been extended beyond week 17 (April 30) for the first time (Figure 2).⁸ Bottom line: We’re still in the 2021-2022 flu season, and patients should be assessed and treated accordingly.

After 2 Mild Influenza Seasons, Are We Due for a More Typical 2022-2023?

Influenza hospitalization rates are lower this season than during those spanning the past decade.^8,9 However, with easing of COVID-19 restrictions, we have the potential to experience the first flu season in 3 years without having significant respiratory countermeasures in place.^10,11 Will influenza become the main driver of infection-related morbidity and mortality, potentially outpacing COVID-19 by the fall? Currently, COVID-19 hospitalizations have risen steadily past their pandemic lows, and it’s anyone’s guess what the summer and fall will hold.¹²

How Will COVID-19 Vaccinations Affect 2022-2023 Influenza Vaccinations?

Although the 2020-2021 season brought the highest influenza vaccination rates ever, the 2021-2022 season thus far seems to have resulted in slightly lower rates of influenza.^4,13 Widespread access to and administration of COVID-19 vaccination(s) may have provided a bit of a boost to the use of influenza vaccinations, as well. Will this fall bring additional COVID-19 boosters? Will people be lax with influenza vaccinations after 2 mild seasons? What about test-to-treat?¹⁴ Will pharmacists gain greater authority or maintain test ordering services with the same level of access and intensity for respiratory infections as they had with COVID-19?

Don't Forget: Reimbursement for Non-COVID-19 Vaccine Administration Increases Substantially for Medicare Patients

Regardless, the Centers for Medicare & Medicaid Services (CMS) has made outreach, counseling, and, ultimately, administration of the influenza vaccination more sustainable. Starting on January 1, 2022, CMS nearly doubled the Part B vaccination reimbursement to $30.15 This move should incentivize pharmacies across the country to become even more vigilant about helping to get that rate of adult vaccine administration back above 50% and beyond. There may or may not be a COVID-19 vaccination push in the fall. Either way, we need to ready our pharmacies for flu vaccine campaigns and to take care of patients—and our community—during the current season.

About the Author

Troy Trygstad, PharmD, PhD, MBA, is vice president of pharmacy and provider partnerships for Community Care of North Carolina, which works collaboratively with more than 2000 medical practices to serve more than 1.6 million Medicaid, Medicare, commercially insured, and uninsured patients. He received his PharmD and MBA degrees from Drake University and a PhD in pharmaceutical outcomes and policy from the University of North Carolina. He also serves on the board of directors for the American Pharmacists Association Foundation and the Pharmacy Quality Alliance.

References

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11. Mask guidance. Centers for Disease Control and Prevention. Updated March 21, 2022. Accessed June 13, 2022. https://www.cdc.gov/ coronavirus/2019-ncov/easy-to-read/mask-guidance.html
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14. COVID-19 test to treat locator. Office of the Assistant Secretary for Preparedness & Response. Department of Health and Human Services. Accessed June 10, 2022. https://aspr.hhs.gov/TestToTreat/Pages/default.aspx
15. Rules and regulations. Department of Health and Human Services. Centers for Medicare & Medicaid Services. Fed Regist. 2021;86(221):64996-166031. Published November 19, 2021. Accessed June 1, 2022. https://www.govinfo. gov/content/pkg/FR-2021-11-19/pdf/2021-23972.pdf