March 21, 2022
The number of influenza cases is increasing across the United States but has not hit pre-pandemic levels, the U.S. Centers for Disease Control and Protection says.
One of the positive side effects of the COVID pandemic was a drop in flu cases, apparently because people were isolating and social distancing. In the 2019-2020 season, more 22,000 people in the U.S. died from flu. Deaths decreased to about 700 for the 2020-2021 season.
For the 2021-22 flu season so far, the CDC estimates there have been 1,700 flu deaths, 2.9 million flu cases, and 28,000 hospitalizations because of the flu.
“The cumulative hospitalization rate … is higher than the rate for the entire 2020-2021 season, but lower than the rate seen at this time during the four seasons preceding the COVID-19 pandemic,” the CDC said in its weekly influenza surveillance report.
But the CDC noted that the number of hospital admissions has gone up each of the last six weeks. Three pediatric deaths from flu were reported last week. For the 2021-22 flu season so far, there have been 13 pediatric deaths.
The percentage of outpatient doctor visits because of respiratory illnesses went up last week, but are still below epidemic baselines, the CDC said, noting that influenza is not the only respiratory illness circulating.
While the number of flu cases varies by location, Oklahoma has reported high flu activity as measured by doctor visits, and Arkansas and Idaho reported moderate activity, the CDC said.
A preliminary study published in December said that flu vaccines for the 2021-22 flu season aren’t providing as much as much protection as hoped for against the most widely circulating strain of influenza. However, the study said it appears the vaccines will still prevent severe illness in people who are infected.
The vaccines were designed far in advance to fight the flu strains expected to dominate the United States during the 2021-22 flu season: H3N2, H1N1, and two strains of influenza B.
Flu season typically lasts from October to May in the northern hemisphere and April to September in the southern hemisphere.