• “Twindemic” now seen as unlikely as flu infections stay low.
Travel restrictions, masks decrease all respiratory illnesses
Despite the horrifying surge of COVID-19 cases and deaths in the United States right now, one bit of good news is emerging this winter: It looks unlikely that the country will endure a “twindemic” of both f lu and the coronavirus at the same time.
That comes as a profound relief to public health officials who predicted as far back as April that thousands of f lu victims with pneumonia could pour into hospitals this winter, competing with equally desperate COVID-19 pneumonia victims for scarce ventilators.
“Overall f lu activity is low, and lower than we usually see at this time of year,” said Dr. Daniel B. Jernigan, director of the inf luenza division of the Centers for Disease Control and Prevention. “I don’t think we can definitively say there will be no twindemic; I’ve been working with f lu for a long time, and I’ve been burned. But f lu is atypically low.”
Since September, the CDC “FluView” — its weekly report on inf luenza surveillance — has shown all 50 states in shades of green and chartreuse, indicating “minimal” or “low” f lu activity. Normally by December, at least some states are painted in oranges and reds for “moderate” and “high.”
Of 232,452 swabs from across the country that have been tested for f lu, only 496, or 0.2 percent, have come up positive.
That has buoyed the spirits of f lu experts.
Dr. William Schaffner, medical director for the National Foundation for Infectious Diseases, which promotes f lu shots, said he was recently on a telephone discussion with other preventive medicine specialists. “Everybody was in quiet awe about how low f lu is,” he said. “Somebody said: ‘Shh, don’t talk about it. The virus will hear us.’”
Flu numbers are likely to remain low for many more weeks, predicted Kinsa Health, a company that uses cellphone-connected thermometers and historical databases to forecast f lu trends.
“Going forward, we don’t expect inf luenza-like illness to go high,” said Inder Singh, Kinsa’s founder and chief executive. “It looks like the twindemic isn’t going to happen.”
A combination of factors is responsible for the remarkably quiet f lu season, experts said.
In the Southern Hemisphere, where winter stretches from June through August, widespread mask-wearing, rigorous lockdowns and other precautions against COVID-19 transmission drove f lu down to recordlow levels. Southern Hemisphere countries help “reseed” inf luenza viruses in the Northern Hemisphere each year, Jernigan said.
Also, to keep COVID-19 out, New Zealand and Australia have closed their borders either to all noncitizens or to Americans, so there has been very little air traffic from those Southern Hemisphere countries.
In the United States, the cancellation of large indoor gatherings, closings of schools and use of masks to prevent coronavirus transmission have also driven down levels of all respiratory diseases, including inf luenza.
In addition, Jernigan said, a “phenomenal number” of f lu shots were manufactured and shipped to pharmacies, hospitals and doctors’ offices in August, a month earlier than usual.
As of late November, 188 million doses had been shipped; the old record was 175 million doses shipped last year. Spot shortages were quickly reported in some cities, so experts assumed that large numbers of Americans took them.
However, there is not yet enough data to confirm that assumption. According to a preliminary tally released Dec. 9, about 70 million adults had received the shots through pharmacies or doctors’ offices as of midNovember, compared with 58 million last year.
Although that appears to be a substantial increase, the CDC does not know how many Americans who normally get their f lu shots at work were unable to do so this year because of stay-athome orders, said Dr. Ram Koppaka, the agency’s associate director for adult immunization. There was a big increase in f lu shots delivered by pharmacies, and that may represent people who normally would have received the shots at work.
“The best we can say is that it appears that we are now about where we were last year,” Koppaka said.
Although Koppaka strongly encouraged unvaccinated Americans to get f lu shots, the threat of a twoheaded pandemic monster appears to be fading.