By John Commins
Fewer than 1,000 cases of the flu have been documented across the United States this season, and the safety precautions taken during the coronavirus pandemic are the likely reason why those numbers are historically low, Johns Hopkins University researchers say.
So far this flu season, 925 cases of influenza have been diagnosed from lab samples submitted to the Centers for Disease Control and Prevention.
In the previous four years that number has averaged 38,280 cases, ranging from 15,026 to 63,975 cases this far into the season, says study coauthor Eili Klein, Ph.D., an associate professor of emergency medicine at Johns Hopkins University School of Medicine.
“More importantly, this gives an estimate based on testing of the percentage of samples that are flu,” Klein says in an email exchange with HealthLeaders. “The average over the last four years has been 10% of samples (a range of 6% to 13%) were positive for flu; this year it is 0.2%. Thus, by either measure, flu cases are about 98% below normal.”
In a typical year, the seasonal influenza runs through May and can cause about 45 million illnesses, hospitalize more than 810,000 people, and claim more than 60,000 lives, according to the CDC.
“In the last four years, there was an average of 38,750 flu-related deaths annually estimated by the CDC, though this varies widely from year to year with a low of 12,000 to a high of 61,000,” Klein says. “This year the estimated number of cases is so low and measures in place to limit transmission of COVID-19 are likely to keep transmission below normal for the foreseeable future.”
Although the seasonal influenza and COVID-19 viruses are different, they are both respiratory viral diseases, Klein says, which means they are spread the same way, and can be contained in the same way through physical distancing, frequent handwashing, virtual work, conferences, and school, and wearing face masks.
“Continued measures to contain spread of COVID-19 will continue to keep rates of influenza low,” he says. “Unless there are significant changes in behavior over the next few months, I would expect the estimated number of deaths to be far below normal, perhaps as low as 1,000.”
Klein says rising public awareness during the pandemic about the potential threats of the seasonal flu have also prompted an increase in the numbers of people getting flu shots, which will also play a big role in reducing flu deaths this season.
While the reduced number of seasonal flu deaths is a rare bright spot during the ongoing public health emergency, Klein warns that the lower number of cases could affect the severity of the next flu season.
“Because of the current restrictions and precautions everyone is taking this season, far fewer people will be infected or exposed to the flu virus, and therefore won’t become immune to certain strains of the virus,” he says. “So the number of people who may have more severe infections next year is likely to be greater because immunity will be lower.”
John Commins is a content specialist and online news editor for HealthLeaders, a Simplify Compliance brand.