NEW YORK (AP) – February is often the peak of the flu season, with doctors’ offices and hospitals crowded with suffering patients. But not this year.
The flu has virtually disappeared from the United States, with reports reaching much lower levels than anything seen in decades.
Experts say that the measures put in place to fight the coronavirus – mask use, social distance and virtual schooling – were a big factor in preventing a “twindemia” influenza and COVID-19. An effort to vaccinate more people against the flu probably helped, as well as fewer people traveling, they say.
Another possible explanation: the coronavirus basically eliminated the flu and other insects that are more common in autumn and winter. Scientists do not fully understand the mechanism behind this, but it would be consistent with the patterns seen when certain strains of flu predominate over others, said Dr. Arnold Monto, a flu expert at the University of Michigan.
Nationally, “this is the lowest flu season we’ve had on record,” according to a surveillance system that is about 25 years old, said Lynnette Brammer of the US Centers for Disease Control and Prevention.
Hospitals say the steady flow of flu patients has never materialized.
At Maine Medical Center in Portland, the state’s largest hospital, “I have not seen any cases of flu documented this winter,” said Dr. Nate Mick, head of the emergency department.
The same is true in the Oregon capital, where respiratory clinics affiliated with Salem Hospital have not seen any confirmed flu cases.
“It’s beautiful,” said Dr. Michelle Rasmussen of the healthcare system.
The numbers are staggering, considering that influenza has long been the country’s biggest infectious disease threat. In recent years, he has been responsible for 600,000 to 800,000 annual hospitalizations and 50,000 to 60,000 deaths.
Worldwide, flu activity is at very low levels in China, Europe and other parts of the northern hemisphere. And that follows reports of little flu in South Africa, Australia and other countries during the winter months of the southern hemisphere from May to August.
The story, of course, is different with the coronavirus, which killed more than 500,000 people in the United States. COVID-19 cases and deaths reached new heights in December and January, before starting a recent decline.
Flu-related hospitalizations, however, are a small fraction of where they would stay even during a very mild season, said Brammer, who oversees the CDC’s screening of the virus.
Influenza mortality data for the entire US population is difficult to compile quickly, but CDC officials maintain a continuous count of child deaths. A pediatric flu death has been reported so far this season, compared with 92 reported at the same point in last year’s flu season.
“Many parents will say that this year their children are as healthy as they ever were, because they are not swimming in the germ pool at school or daycare in the same way they were in previous years,” said Mick.
Some doctors say they have even stopped sending samples for testing because they don’t think the flu is present. However, many laboratories are using a “multiplex test” developed by the CDC that checks samples for coronavirus and flu, said Brammer.
More than 190 million doses of flu vaccine have been distributed this season, but the number of infections is so low that it is difficult for the CDC to make its annual calculation of how well the vaccine is working, Brammer said. There is simply not enough data, she said.
This is also challenging next season’s flu vaccine planning. This work usually starts with checking which flu strains are circulating around the world and predicting which ones are likely to predominate in the coming year.
“But there are not many (flu) viruses to examine,” said Brammer.
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