Confusion permeates the interweb when it comes to masks and COVID-19 vaccines.
I know this is shocking, but despite Doug’s “Wear a Mask” public service announcement video there are lots of anti-maskers still out there, especially in Tampa Bay, and every day in my office I encounter patients and family members who are not eager to get vaccinated.
Legitimate questions remain about the nuances of mask wearing including:
- Do I need to wear a mask after vaccination?
- Should I double mask?
- What’s the best double masking technique?
An excellent podcast on JAMA Clinical Reviews with John T. Brooks, MD, chief medical officer of the CDC’s COVID-19 response team answers these questions and more. Brooks also reviews recently published epidemiologic data that reinforce the role of mask use for pandemic control.
Listen to the podcast here
Related Article:
Effectiveness of Mask Wearing to Control Community Spread of SARS-CoV-2
Dr. Monica Gandhi gave Grand Rounds at UCSF focused on the new vaccines and discussed how we should behave when we are in a group of fellow post-vaccinees.
Dr. Gandhi believes we can relax restrictions following vaccination and the lucky post-vaccinated can mingle with each other:
Gandhi and a colleague published their paper on the dual cloth and medical procedure mask (cloth on the outside) approach which they feel approaches 90% reduction of transmission and should be employed when maximal protection warranted:
Get your COVID-19 vaccine ASAP (any one you can get) and please keep on masking.
-ACP
4 thoughts on “The Latest on Masks and Vaccines”
On the effectiveness of masks, most of the evidence used in support of masks is weak. Either in study design, sample size, or statistical significance one can find many shortcomings. In the paper cited above (“Effectiveness of Mask Wearing to Control Community Spread of SARS-CoV-2”), none of the studies in the table are randomized clinical trials. Many are small sample sizes. Many have very weak results. Several utilize “self-reporting” for their methods. Most citing public mandates for mask wearing ignore that compliance for mask wearing up to the point at which it was made obligatory was already extremely high. I’m yet to see anyone address what would appear to be the most rigorous study on the topic: DANMASK-19 (Link to full text: https://www.acpjournals.org/doi/10.7326/M20-6817). It is a randomized clinical trial with 2994 subjects in the control group and 3030 participants randomly selected to wear masks. 4862 completed the study. The masks were all surgical masks, which is already a step up from most studies where the masks are not uniform. This excludes gaiter neck masks and others that have not been shown to be beneficial. The test group was also given instruction on how to use the surgical masks, another point of control which other studies do not have. Participants spent an average of 4.5 hours/day outside the home. And so on. I’d suggest reading the full study to appreciate the rigor with which the researchers employed to control as many variables as possible.
The results: Infection with SARS-CoV-2 occurred in 42 participants recommended masks (1.8%) and 53 control participants (2.1%).
To my knowledge, this is the most well-controlled and well-designed study on masks to date and the conclusion would not lead one to believe that masks provide significant benefit in protection against SARS-CoV-2. There are other studies that do not lend support to the efficacy of masks in the non-hospital setting (see this systematic review of 14 RCTs on masking to prevent influenza from 5/2020: https://wwwnc.cdc.gov/eid/article/26/5/19-0994_article), but this has the strength that many of the studies in favor of masks have not, giving it’s conclusion much more force.
Anthony A.
Anthony,
Thanks for your comments. The DANMMASK trial does suggest that wearing a surgical mask in an environment where others are unmasked doesn’t cut down infection rate. And it was an RCT, the highest level of evidence. There are limitations and it doesn’t apply to the combination of source masking and target matching. The authors state
The findings, however, should not be used to conclude that a recommendation for everyone to wear masks in the community would not be effective in reducing SARS-CoV-2 infections, because the trial did not test the role of masks in source control of SARS-CoV-2 infection. During the study period, authorities did not recommend face mask use outside hospital settings and mask use was rare in community settings (22). This means that study participants’ exposure was overwhelmingly to persons not wearing masks.
Thanks for the post Dr. Pearson! I understand why medical experts may have an instinct to obfuscate in terms of sharing good science that points to vaccinated people hanging out together unmasked safely, but with the science on our side, treating adults like kids is not a recipe for success in a public health emergency, even if many of them are acting like children. The “don’t wear masks debacle” at the start of the pandemic is one clear example, as is the former Presidents approach to “not wanting to cause panic”, as he stated to Woodward. The truth will set you free.
Celebrate this news! It’s a big deal, and we have science to thank. Also, promising developments on potential lack of transmittal of vaccinated people and vaccine efficacy with the known variants.
My CCRC community (in the San Francisco Bay area) of about 850 residents in independent living had the opportunity to get the Pfizer vaccine – 1st dose about 1-11-21 and 2nd about 2-1-21. Approximately 98% of residents opted for the vaccine. Our employees and vendors were also eligible. Only 66% opted in January, but the % went up to 75% this month. Residents are mostly white or Asian; lower end employees and gardeners (we hire their firm) mostly Hispanic immigrants. There have been only 2 known COVID-19 cases among residents which originated here; two others were on the Grand Princess last Feb. and were not able to return here until cured. It seems the better educated are much more likely to opt for the vaccine and are also more likely to wear masks and take other precautions. the less educated need to be inspired and encouraged by members of their own communities who listen to responsible authorities.