Is the Delta variant making masks less effective, but more significant?

 Last update: Saturday 7/17/21

Wearing masks reduces the spread of the coronavirus through unvaccinated communities, but by how much? Rigorous clinical trials showed that the Moderna and Pfizer vaccines were 95% effective. Unfortunately there are no reliable estimates of the effectiveness of masks. So why do sensible people wear masks? Common sense suggests two reasons: (1) our prior personal experience with colds and the flu, and (2) our desire to use our masks to provide visible reminders to others that COVID is still a threat in some local communities. The highly contagious Delta virus (and more lethal variants yet to come) may render our prior experience less relevant, but will underscore the value of our masks as reminders.

The pandemic's uneven start and finish

The COVID pandemic began unevenly, infecting only a few states in February 2020. Unfortunately, the CDC panicked and tried to lock down the all fifty states. The CDC's recommended guidelines should have reflected the differing prevalence of the virus in different states

Ironically, the pandemic is ending more unevenly than it started, with high vaccination levels in some communities and low levels in other communities within the same states. Unfortunately, the CDC panicked once again and tried to open up the entire country before the July 4th holiday, saying that people who were vaccinated no longer had to wear masks or maintain social distancing in most situations. 

This time we should not let our behavior be determined by the confused folks at the CDC but by the local prevalence of our highly effective vaccines. Of course, residents and visitors in local communities having low vaccination levels should continue to follow the standard mitigation guidelines -- social distancing, avoiding large groups, frequent hand washing ... and masks.

• "Delta Variant Widens Gulf Between ‘Two Americas’: Vaccinated and Unvaccinated", Apoorva Mandavilli and Benjamin Mueller, NY Times, 7/14/21

Prior experience vs. the Delta variant

Children are taught to cover their mouths when they cough or sneeze in order to prevent their germs from infecting the people around them. Many people were relieved when the task force and CDC reversed themselves in April 2020 and told us to cover our mouths all of the time with masks, which was consistent with what they had been taught to do as children. The task force and CDC were quick to point out that non-N95 masks would not guarantee that mask wearers would be protected; however masks would substantially reduce the number of people in a group who became infected. 

Nevertheless the question about the effectiveness of masks still remains: by how much do masks reduce the spread of the virus? By 50 percent? 25 percent? 10 percent? No consistent estimates have been provided. Common sense suggests that 50 percent, as good as the FDA minimum for approving vaccines, is way too high, whereas 10 percent would provide minimal resistance to the spread of the virus. So if pressed, it's likely that most people would guess that the effect would be closer to 25 percent.

Now comes the Kraken, the monster Delta variant that is far more contagious than previous variants. How effective are masks against the Delta? Closer to 10 percent? If so, less emphasis should be placed on masks in low vaccination communities, and more on social distancing, perhaps at greater than six feet, where possible. 

Masks as reminders

Even if masks become less effective at blocking the spread of Delta and other highly contagious variants, they will become far more important as visible reminders in low vaccination communities that the pandemic is not over for these communities. Hopefully, these reminders will nudge unvaccinated members of these communities to continue to wear masks, wash their hands frequently, maintain social distancing, avoid large groups, etc, etc, etc ... and, most importantly, become vaccinated as soon as possible.

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Related notes on this blog:

• "The pandemic is almost over according to our major media, but for whom?", Last update: 7/16/21
  
  
• "An open letter to President Biden regarding the critical need to reorganize the CDC immediately", Last update: 6/17/21