At the outset of the pandemic in 2020, nearly every major health authority in the world sort of just decided that masks were extremely effective and extremely necessary at combating COVID-19. So we all had to wear masks for literal years.
Now, a major health database reportedly shows that masking really didn't do that much at all:
Earlier this week, the Cochrane Library released a sweeping update of its evidence summary of physical interventions to reduce the spread of respiratory viruses. For context, every academic physician has heard of the Cochrane Library, as their database is where medical evidence "lives." If you are looking at any particular medical intervention and you want to know how effective it is, your first stop would be the Cochrane Database: the gold standard for evidence-based medicine.
Cochrane touts itself as "a collection of databases that contain different types of high-quality, independent evidence to inform healthcare decision-making." It's mainstream, respected, trusted, well-funded. It claims its CDSR database is "the leading resource for systematic reviews in health care."
So when they make this kind of pronouncement, you can pretty much take it to the bank:
First, the study showed there is no difference between wearing N95 respirators versus loose-fitting masks in medical settings.
There is uncertainty about the effects of face masks. The low to moderate certainty of evidence means our confidence in the effect estimate is limited, and that the true effect may be different from the observed estimate of the effect. The pooled results of RCTs did not show a clear reduction in respiratory viral infection with the use of medical/surgical masks. There were no clear differences between the use of medical/surgical masks compared with N95/P2 respirators in healthcare workers when used in routine care to reduce respiratory viral infection.
Second, the study showed that wearing masks in public at large makes no difference:
We included 12 trials (10 cluster‐RCTs) comparing medical/surgical masks versus no masks to prevent the spread of viral respiratory illness (two trials with healthcare workers and 10 in the community). Wearing masks in the community probably makes little or no difference to the outcome of influenza‐like illness (ILI)/COVID‐19 like illness compared to not wearing masks (risk ratio (RR) 0.95, 95% confidence interval (CI) 0.84 to 1.09; 9 trials, 276,917 participants; moderate‐certainty evidence. Wearing masks in the community probably makes little or no difference to the outcome of laboratory‐confirmed influenza/SARS‐CoV‐2 compared to not wearing masks (RR 1.01, 95% CI 0.72 to 1.42; 6 trials, 13,919 participants; moderate‐certainty evidence)
As a reminder for those who have been paying attention:
In her analysis of the findings, Dr. Kristen Walsh writes:
As others have observed, it may still make sense for doctors to counsel immunocompromised or medically vulnerable individuals to wear masks during cold and flu season. This is because interventions that are not effective at a population level may still provide some benefit to individuals at risk. But in my opinion, this meta-analysis should put a permanent end to mask mandates. We cannot impose on people's freedom and bodily autonomy to mandate an intervention that shows no efficacy at a population level. Further, given the possibility that masks could provide some protection to vulnerable individuals, any protection would be for that individual only and does not require mandating others to act in a certain way.
