NEW YORK (AP) – February is usually the peak time of the flu season, with medical offices and hospitals full of patients suffering. But not this year.
The flu has virtually disappeared from the United States, with reports reaching levels far below those seen in decades.
Experts say the measures put in place to defend the coronavirus (the use of masks, social distancing and virtual schooling) were an important factor in preventing a “twindemia.” of influenza and COVID-19. A push to vaccinate more people in the flu probably also helped, as they say, fewer people traveling.
Another possible explanation: the coronavirus basically has musculature apart from the flu and other more common insects in the fall and winter. Scientists do not fully understand the mechanism behind this, but it would be consistent with the patterns seen when certain flu strains predominate over others, said Dr. Arnold Monto, a flu expert at the University of Michigan.
Nationwide, “this is the lowest flu season we’ve seen,” according to a surveillance system about 25 years ago, said Lynnette Brammer of the U.S. Centers for Disease Control and Prevention.
Hospitals say the steady flow of flu-affected patients never materialized.
At Maine Medical Center in Portland, the state’s largest hospital, “this winter I saw zero documented flu cases,” said Dr. Nate Mick, head of the emergency department.
Same in the capital of Oregon, where outpatient clinics affiliated with Salem Hospital have not seen any confirmed cases of flu.
“It’s beautiful,” health system doctor Michelle Rasmussen said.
The figures are staggering given that the flu has long been the biggest infectious disease threat in the country. In recent years, he has been charged with 600,000 to 800,000 hospitalizations annually and 50,000 to 60,000 deaths.
Worldwide, influenza activity has been at very low levels in China, Europe, and elsewhere in the northern hemisphere. And this follows reports of low flu in South Africa, Australia and other countries during the winter months of the southern hemisphere from May to August.
The story, of course, has been different with the coronavirus, which has killed more than 500,000 people in the United States. COVID-19 cases and deaths reached new levels in December and January, before a recent decline began.
However, flu-related hospitalizations are a small fraction of where they would be even during a very mild season, said Brammer, who oversees the CDC’s monitoring of the virus.
Influenza death data for the entire U.S. population are difficult to compile quickly, but CDC officials maintain a current count of child deaths. So far this season a pediatric flu death has been reported compared to 92 recorded at the same time last year’s flu season.
“A lot of parents will tell you that this year their kids have been as healthy as ever, because they don’t swim in the germ pool at school or in daycare the same way they did in previous years,” Mick said.
Some doctors say they have even stopped sending samples to test them, because they don’t believe there is a flu. However, many labs use a “multiplex test” developed by CDC that checks samples for both coronavirus and flu, Brammer said.
More than 190 million doses of flu vaccine were distributed this season, however, the number of infections is so low that it is difficult for the CDC to make the annual calculation of vaccine performance, Brammer said. There just isn’t enough data, he said.
This also poses a challenge for next season’s flu vaccine planning. This work usually begins by checking which strains of influenza are circulating in the world and predicting which of them will probably predominate next year.
“But there aren’t a lot of (flu) viruses to look at,” Brammer said.
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The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.