As Covid-19 continues to grow in the United States, with a record number of more than 4,000 virus deaths on Friday, some good news came from data on the flu.
During a typical flu season, the number of people catching the flu would start to increase, with the peak occurring normally in February. However, so far, only 0.2% of the 400,000 swabs for flu have been positive, according to data from the Centers for Disease Control and Prevention. At the same time last year, the positivity rate was 13%.
With hospitals across the country close to or with capacity for Covid-19 patients – some 132,000 people are currently hospitalized with Covid – the minimal presence of influenza is a blessing. At least 38 million Americans contracted the virus during the 2019-20 season. Although the flu is less deadly than Covid-19, it has the potential to damage the health care system during a bad year. Last year, 400,000 people were hospitalized with the flu and 22,000 died of it.
“Covid is causing incredible stress on the healthcare system in many parts of the country,” said Dr. William Schaffner, professor of preventive medicine and infectious diseases at Vanderbilt University. “Even if we had a light to medium [flu] season, we would all be flooded at the moment. “
Instead, “we are having a profoundly mild flu season so far,” said Schaffner.
Several factors have contributed to cushioning the flu this season.
The virus usually reaches the northern hemisphere after spreading in the southern hemisphere, which lives its flu season from June to August. But the 2020 flu season in the south was virtually non-existent.
Public health experts believe that measures in the southern hemisphere to prevent the spread of Covid-19 have also worked to prevent the spread of flu. Although influenza is also a respiratory virus, it is not as transmissible as Covid-19, so masking and social detachment are more effective at stopping the spread of flu than the spread of Covid-19. The low number of cases, coupled with the decrease in travel between the northern and southern hemispheres, bodes well for the flu season in the north.
Still, Americans were urged to get the flu shot to lessen the chances of a dreaded “twindemia” of flu and Covid-19. More than 192 million doses of the flu vaccine were distributed across the United States by the end of December, according to the CDC, the highest number of doses distributed in a single flu season.
It appears that most of these doses have been used. More adults in the U.S. received the vaccine this season compared to previous years, according to the CDC. About 53% of adults received flu vaccines. At the same time last year, 42% of adults were vaccinated, while 48% were vaccinated at the end of the last flu season.
Schaffner said that schools that take steps to prevent the spread of Covid-19 – extensive cleaning, masks and social detachment and taking classes virtually – have probably also played an important role in combating the spread of flu. Children spread the flu virus more than adults and for longer periods, making it easier to spread to family members and teachers who can pass it on to other adults.
“Children were much more isolated, so this distribution mechanism has effectively ended,” he said.
While there is much to celebrate about the low numbers of the flu, the United States is not yet out of danger: there is still a chance that the virus will see an increase, especially since millions of Americans have traveled over the holidays.
But Schaffner said there was cautious optimism that the United States had avoided the worst of a “twindemia”.
“We remain very alert to this possibility, but so far, I think we are at a record pace for a low flu season.”