FALL FLU FORECAST. A sign advertising flu and COVID-19 shots, left photo, is viewed outside a Walmart Supercenter in Ocoee, Florida, on August 10, 2022. Drawing on global trends, Oregon Health & Science University (OHSU) is forecasting potential for a vigorous return of influenza after a two-year dip. Influenza may outpace COVID-19 infections in driving hospitalizations in Oregon during the fall and winter, according to a recent OHSU statewide biweekly forecast. (Phelan M. Ebenhack via AP)

Pictured are vials of the Moderna COVID-19 vaccine. (Photo/Oregon Health & Science University)

Drawing on global trends, Oregon Health & Science University (OHSU) is forecasting potential for a vigorous return of influenza after a two-year dip. Influenza may outpace COVID-19 infections in driving hospitalizations in Oregon during the fall and winter, according to a recent OHSU statewide biweekly forecast.

The forecast continues to show a steady decline in the number of hospitalized patients with COVID-19 in Oregon. A total of 253 people were hospitalized with COVID-19 as of September 14, with the OHSU forecast projecting the number continuing to decline through the end of October, until picking up again in November as immunity wanes and people increasingly gather indoors.

The recent forecast raises a more pressing concern about influenza — a virus that has been all but absent for the past two-and-a-half years.

Peter Graven, Ph.D., director of the OHSU Office of Advanced Analytics, said that receiving a flu vaccine is "extremely important this year, certainly more than it has been in the last two years when we had virtually no flu that was circulating. The flu is probably going to be at least as important this year as COVID."

Graven cited relatively high rates of influenza starting early in some areas of the Southern Hemisphere, where influenza typically circulates in their winter months, from April to October.

The public’s willingness to wear masks, limit indoor gatherings, and take other public health measures limited the spread of COVID-19 over the past two-and-a-half years, said Dawn Nolt, M.D., M.P.H., professor of pediatrics (infectious diseases) in the OHSU School of Medicine.

All of those public health measures also minimized the circulation of flu.

Nolt noted that the lack of exposure to influenza over the past two years also means that people’s immune systems lack practice in fighting off the influenza virus. This, in turn, portends a potentially vigorous flu season when the virus circulates this fall and winter.

"In normal years, lots of people are exposed to the flu, which provides a natural boost to their immune response," Nolt said. "We haven’t seen much flu at all in the past three years. That makes it really important to get yourself vaccinated against flu this season."

Flu vaccines are widely available at pharmacies and through healthcare systems across the region.

In addition to the availability of the flu vaccine, the new bivalent booster vaccine against COVID-19 has arrived in Oregon and is widely available. The bivalent booster targets the BA.4 and BA.5 omicron variants, along with the original strain of the SARS-CoV-2 virus that causes COVID-19.

The current number of COVID-19 cases is far below the 1,178 people hospitalized with COVID-19 during the peak of the delta variant wave, as of September 1, 2021 last year.

Nolt encourages people to get both the COVID-19 booster and annual flu shot as soon as they are eligible.

To learn more, visit <www.ohsu.edu/health/coronavirus-resources#section-1349461>.