Fears of a deadly ‘twindemic’ recede
Despite the horrifying surge of COVID-19 cases and deaths in the United States right now, one bit of good news is emerging for the winter: It appears unlikely that the country will endure a “twindemic” of both flu 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 flu victims with pneumonia could pour into hospitals this winter, competing with equally desperate COVID-19 victims for scarce ventilators.
“Overall flu activity is low, and lower than we usually see at this time of year,” said Dr. Daniel B. Jernigan, director of the influenza 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 flu for a long time, and I’ve been burned. But flu is atypically low.”
Since September, the CDC “FluView” — its weekly report on influenza surveillance — has shown all 50 states in shades of green and chartreuse, indicating “minimal” or “low” flu 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 flu, only 496, or 0.2%, have come up positive.
That has buoyed the spirits of flu experts.
Dr. William Schaffner, medical director for the National Foundation for Infectious Diseases, which promotes flu shots, said he was recently on a telephone discussion with other preventive medicine specialists.
“Everybody was in quiet awe about how low flu 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, predicts Kinsa Health, a company that uses cellphone-connected thermometers and historical databases to forecast flu trends.
A combination of factors is responsible for the remarkably quiet flu 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 flu down to recordlow levels. Southern Hemisphere countries help “reseed” influenza viruses in the Northern Hemisphere each year, Dr. 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 U.S., 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 influenza.
In addition, Dr. Jernigan said, a “phenomenal number” of flu 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 mid-November, compared with 58 million last year.
Nonetheless, even the preliminary data showed disturbing trends in two important target groups: pregnant women and children. Only 54% of pregnant women have received the flu vaccine this year, compared with 58% by this time last year. And, although about 48% of all children got flu shots both last year and this year, the percentage of Black children who got them dropped substantially this year, by 11 percentage points.