More and more science shows mask-wearing is effective

Everywhere you turn, the mask debate rages on. I personally seem to address the topic daily—even amongst my patients. And this certainly isn’t be the first time we’ve talked about it here

As you know, I turn to scientists—not politicians and pundits—to give me answers to medical questions such as these. But as I explained on Tuesday, the line between fact and opinion has always been dangerously blurry to the public on this particular issue.

That’s why, today, I’m going to present three recent studies that show that wearing a mask is absolutely, undeniably effective in reducing the transmission of COVID-19. In fact, these studies demonstrate very clearly that, when everyone wears a mask, the transmission rate drops significantly.

Wearing a mask makes a difference

The first of these studies looked at the impact of a range of interventions—universal masking, handwashing, and personal protective equipment (PPE) use on COVID-19 positivity rates among healthcare workers.

The majority of these healthcare workers had direct patient contact, but did not work within dedicated COVID-19 units.

When researchers tested all symptomatic workers for the virus, they found an overall positivity rate of 2.8 percent. But they also found reductions in case rates among healthcare workers with universal masking, PPE use, and less contact with unmasked employees.

Another study tested positivity rates among nearly 10,000 healthcare workers in the northeastern U.S. both before and after universal masking of workers and patients was mandated. And results revealed similar trends.

Before these protective interventions, positivity rates among healthcare workers jumped from zero to over 20 percent, with cases doubling every few days. After interventions, though, those positivity rates dropped steadily—and significantly.

A community service

The third study was a little different: Researchers attempted to identify whether new COVID-19 infections had been acquired in the community or in a healthcare setting via phone interviews with sick healthcare workers.

Then, they compared infection rates among these healthcare workers—most of whom did not work on COVID-19 units—both before and after universal masking mandates.

Researchers determined that 38 percent of cases were acquired from community exposure, 22 percent came from a healthcare setting, and 40 percent were of unclear origin.

They also determined that—among healthcare-linked cases—a whopping 70 percent were traceable to unmasked exposure to colleagues. (Meanwhile, only 30 percent were related to direct care of COVID-positive patients.)

Needless to say, within a week of universal masking in healthcare settings, there was a significant drop in infection rates among healthcare workers. And considering that the majority of these infections were community-acquired, it’s safe to assume that those infection rates drop even further with a universal mask mandate for everyone who ventures out into public spaces.

How much clearer does the evidence have to get? And how many more people have to die because some people don’t want to be “inconvenienced” by wearing a mask in public?

As I write this, we are at nearly 200,000 American lives lost to this pandemic, with no clear end in sight. So no matter who tells you that masks aren’t necessary, remember that the scientific facts say otherwise.

P.S. For additional ways to stay healthy during the coronavirus pandemic, take a look at my Complete Guide to Year-Round Immunity. This comprehensive report outlines all of my top immune health recommendations. Click here to learn more!


“Studies Track Infections to Measure Mask Effectiveness.” Medscape Medical News, 08/14/2020. (