Regardless of your personal opinions of COVID-19 and the precautions we could or should take, there have been some inarguably beneficial effects of the COVID precautions taken over the last year. The most profound effect, as you might guess from the title of this article, was on the 2020–2021 flu season. It is this writer’s belief that the effects on the flu alone are enough to warrant continued use of masks daily, even after the COVID health crisis has passed.
Prevalence of the Flu
First, let’s look at previous years. Historically, the flu is so common (and so commonly undiagnosed) that we can only estimate the number of people who contract it. Analysts use a range of models to make these estimates as accurate as possible (such as those discussed here), but experts in every field can agree that we have a lot of flu each year. The fact that “flu season” is a daily term for English speakers in late fall and winter each year testifies to a complete cultural awareness of the prevalence of the flu, and the commonness of its transmission.
Specific years range from 9.3 million to 45 million cases, with between 12,000 and 61,000 deaths each flu season. (Full data here.) In 2010, 6.6% of Americans had symptoms from the flu virus. In 2019, that percentage was 12%, nearly double 2010’s rates. It’s important to understand that this number has peaks and valleys, and you can see the full data of these things in the link above. Even taking that into consideration, cases increase as a trend. That is, until COVID-19 hit.
Effects of COVID Precautions
As COVID-19 precautions began to be implemented by individuals, businesses, and governments, flu and other respiratory illnesses saw a steep drop. The CDC’s topmost flu tracker, Lynnette Brammer, indicated that the prevention measures implemented in the spring coincided with a sharp drop in flu infection rates. Where it gets particularly noteworthy, however, is when we look at the 2020–2021 flu season. First, we should note that people are still getting the flu tests in hospitals when they are sick. It’s just that they’re almost all coming back negative. Before the precautions were in place, about 20% of flu tests came back positive. In April (after precautions were implemented) that number dropped to less than 1%, and stayed there, even though people were still getting the tests. If few-to-no tests had been administered, we might have been able to hand-wave the issue as a lack of tests, but since people were getting tested, that cop-out isn’t available.
In December 2019 alone, the CDC’s lab (FluVue) reported 50,526 positive cases of the flu. In December of 2020, that number was 454, a reduction of over 99%. This is a staggering success for the reduction of illnesses that kill babies and the elderly at disproportionate rates. Similar data has been observed worldwide for RSV or respiratory syncytial virus, which is best known for giving infants and older adults deadly cases of bronchitis and pneumonia, but can affect anyone of any age.
What Happens When We Stop Taking Precautions
Frighteningly, there are large breakouts of respiratory illnesses like the flu and RSV in countries that are currently able to relax COVID-19 restrictions. While the data cannot definitively say that people gathering without masks are to blame, the timing is in lockstep. Countries like Australia are facing off-season outbreaks larger than the normal outbreaks they’d have, which may lead to more deaths than an average year. New South Wales in Australia recently had 6,000 positive RSV cases in two weeks, 1,300 more cases than entire month of their previous seasonal peak in 2019. This pattern may play out in other countries around the world, so it makes sense to wear masks to delay the spread of these other illnesses, as well.
The flu kills 30–40,000 Americans in an average year, when agencies like the CDC deem it “safe” to take no precautions. With social distancing, mask wearing, and other precautions, that number has dropped considerably. Only 450 Americans died from the flu in the 2020-2021 flu season, with only 1,500 total cases despite a steady number of flu tests being administered compared to previous seasons. The precautions we’re already fluent in have the capacity to nearly eliminate flu and respiratory illness deaths nationwide. Keep washing your hands. Keep wearing masks. If 525,000 deaths in one year from COVID-19 aren’t enough, think of the 50,000,000 (yes, 50 million) deaths caused by the flu in 1918. We can prevent that ever happening again, too.
If you want to see the marvels of modern medicine, they’re right here. Masks and handwashing are facets of your daily healthcare that you have direct control over, are accessible whenever you need them (so long as you’re prepared), and are incomparably effective. Save lives. Save money. Protect children. Live confidently, live safely, go back to normal—with more tools at hand.