The Flu Season May Yet Turn Ugly, CDC Warns



Donald G. McNeil Jr.

c.2020 The New York Times Company


The United States may be headed into a bad flu season, according to figures recently released by the Centers for Disease Control and Prevention.

As of the last week of December, “widespread” flu activity was reported by health departments in 46 states. More ominously, a second measure — the percentage of patients with flu symptoms visiting medical clinics — shot up almost to the peak reached at the height of the 2017-18 flu season, which was the most severe in a decade.

About 61,000 Americans died of flu that season, the CDC said. (The original estimate of 79,000 was revised downward last year; the agency said the number changed as more death certificate information became available.)

This year’s flu vaccine may not be particularly effective against the strain of the virus now widespread in the United States, experts said. But even so, it’s worth getting the shot: People who are vaccinated fare better if struck by the flu than those who are not.

It is still too early to know how severe this season will be, said Lynnette Brammer, leader of the agency’s domestic influenza surveillance team.

Although many people are coming down with flu, the two chief indicators of severity — hospitalizations and deaths — are not yet elevated, she noted.

The current season did begin unusually early. By late November, the flu had hit hard in the Deep South, from Texas to Georgia. The virus then broke out in California and the Rocky Mountain states, but was not widespread in the Northeast until recently.

That pattern echoes what happened in Australia. Flu came unusually early to the Southern Hemisphere in 2019.

In another important way, however, the United States is not following Australia’s lead. The A(H3N2) strain of influenza was dominant there last year, while most U.S. cases this season have been caused by a very different strain, called B Victoria. (B strains are named for the cities where they were first isolated.)

B strain flus do not normally arrive until late in the season. But when they do, “they often impact children more than adults and older adults,” Brammer said.

Thus far this season, 27 children have died of flu — in 2017-18, 187 died — but pediatric deaths don’t normally start peaking until mid-January.