Flu infections have been unusually low this season during the COVID-19 pandemic, and one child has died compared to more than 100 at this time last year.
“The basis for this low activity is likely multifactorial and it’s likely that COVID-19 mitigation strategies played a role,” said Lisa Grohskopf, M.D., M.P.H., from the Centers for Disease Control and Prevention’s (CDC’s) Influenza Division. “Things such as use of masks, social distancing, school closures and there having been less travel or more restricted travel than usual.”
During the week ending Feb. 13, about 1.1% of outpatient visits were for flu, according to the CDC. That figure has been below the baseline of 2.6% all season, although the CDC cautioned that some people may be seeking care in other settings. Only 0.1% of respiratory specimens at clinical laboratories tested positive for flu during the week ending Feb. 13.
The cumulative hospitalization rate of 0.6 per 100,000 people is the lowest since reporting began in 2005.
The numbers are so low the CDC could not provide an estimate of vaccine effectiveness it usually releases at this time of year. However, Dr. Grohskopf presented data to the CDC’s Advisory Committee on Immunization Practices on Thursday showing the racial disparity in children receiving flu vaccines. Coverage was 58% for White children, 53% for Hispanic children, 44% for Black children and 58% for other non-Hispanic races as of Jan. 16. Overall, about 55% of all children were vaccinated compared to 56.5% at the same time last year.
Despite the low flu activity, experts said they could not predict what would happen this spring or next season and continue to recommend everyone 6 months and older get vaccinated.
The CDC currently discourages use of any other vaccine within 14 days of a COVID-19 vaccine due to a lack of safety and efficacy data. A study planned for next flu season will look at simultaneous and sequential administration of COVID and flu vaccines in adults.