The mask worked all the time

The most urgent questions in the world over the last 20 months are: What is the best way to stop the spread of the coronavirus? But even the most logical solution is wrapped in what I’m calling, so the clear answer is a frustrating question. Pandemic fog..

For example, covering the nose and mouth seems like a wise way to block viral particles that come out of the mouth and enter the nose. However, it is difficult to design a perfect masking study if state-by-state behavior differs from official masking policies, and if everyone wears different materials on the face. Restricting indoor diets seems to help contain the virus that spreads through indoor conversations, but of high quality enough to ensure that it makes a big difference. there is no data. Targeted shutdowns are likely to prevent social mixing in the short term, but designing experiments to prove long-term effectiveness is devilishly difficult.

In contrast, studies demonstrating the efficacy of the COVID-19 vaccine used the gold standard of scientific research by randomly assigning people to treatment and control groups and carefully measuring the effectiveness of medical interventions. .. For example, if there was something like this about masking, it would be a carefully randomized, real-world experiment with the effects of masking.

Well, now we have it. This week, a group of scientists from Yale University, Stanford University, the University of California, Berkeley, and other institutions announced the final results of a randomized study of community-wide masking behavior in Bangladesh. About 350,000 people participated in this survey in 600 villages. Researchers give out free masks, pay to remind villagers to cover their faces, and encourage religious figures such as village leaders and imams to emphasize the importance of masks. A specific village was randomly selected. Researchers also paid villagers to count properly worn masks in public places such as markets and mosques. To collect data on coronavirus infection, the team asked about symptoms and performed blood tests to determine who was infected with COVID-19 during the course of the study.

Read: The vaccine is great. Masks make them even better.

What are their conclusions? The mask works, the period. Surgical masks are especially effective in preventing coronavirus infection. Also, wearing masks throughout the community is good for protecting older people who are at much higher risk of serious illness from COVID-19.

To some, this conclusion may sound like the work of a liberal conspirator who permanently wraps our face in a tyrannical cloth. To others, it may sound like very old news. After all, if people were successfully masking during the 1918 flu epidemic, you might wonder why a 2021 study is needed to prove the benefits of this practice. However, Bangladesh studies may be the most important studies conducted during a pandemic other than vaccine clinical trials. This is to provide randomized trial data that support the flimsy assumptions and conclusions of observational studies.We finally have the feeling that it’s not just Somehow Although the mask works ikura Universal masking has the potential to reduce infections. The answer is: quite a lot.

The randomly assigned promasking policy reduced the number of symptomatic COVID-19 cases identified in the intervention group by almost 10% compared to the control group. It may not sound like a big effect. However, the intervention increased masking from 14% to 43%. 100% masking could have had a much greater effect.

Even more striking, in villages that implemented pro-masking policies, COVID-19 was reduced by 34% among the elderly, who are most deadly to the disease. This may be because older villagers are more likely to wear masks properly, or because they are more likely to develop a symptomatic infection when in contact with the coronavirus.

The study also found clear evidence that surgical masks are superior to cloth masks in reducing the spread of symptomatic COVID-19. Focus groups said Bangladeshi participants prefer cloth masks because they appear to be durable. However, researchers, on the other hand, found that surgical masks were more efficient, even after washing 10 times with soap and water. “On the other hand, we found only a lot of evidence about cloth masks,” Jason Abulk, co-author of the study and professor at Yale University, told me. People wearing cloth masks had fewer symptoms such as coughing than the control group, suggesting that they had some effect. However, wearers of cloth masks were not significantly low in coronavirus antibodies, as determined by blood tests. “We can’t refuse it [cloth masks] The effect on symptomatic SARS-CoV-2 infection is zero or minimal, “written with Mushfiq Mobarak of Yale University, Laura Kwong of the University of California, Berkeley, Stephen Luby and Ashley Styczynski of Stanford University, and other researchers. I am.

Creating social norms is a daunting task. The promasking interventions in this study were aggressive, extensive, and costly. In total, researchers have distributed over a million masks. Free distribution of masks was important. But of all the interventions, the promotion of masks, that is, paying individuals to remind people in the street to cover their faces, seemed to be most effective. “Reminders from the villagers almost acted as masking booster shots,” Avalak told me. The research team is currently working on expanding interventions in countries such as Pakistan, India and Nepal.

Read: The mask is back, probably in the long run

In Bangladeshi studies, subtle efforts to change behavior have not been very effective. Text message reminders made little difference. Talking about altruism and protecting the community made little difference. Offering cash rewards made little difference. It made little difference to post a sign of a professional mask to people or ask them to verbally promise to wear a mask in the future. The action nudge could not nudge the action.

Those who have a strong opinion about masks need to be careful about how they incorporate this study into their advocacy. For discussions about masks in primary school, this study is rarely provided directly, as surveillance staff recorded mask-wearing behavior only among people over the age of 18. This study also does not apply directly to crowded arenas about discussions about masking in certain places, such as cinemas. “Our study cannot distinguish between outdoor and indoor infections,” said Avalak. “Given other studies, masks may be most effective in indoor, unventilated spaces. However, in our study, for example, parks, restaurants and schools could be places of transmission. It is not clearly indicated whether it is high or not. “

So where does this leave us? Over the past year and a half, US masking has become a flash point for parties from a point of turmoil. Republicans who discover a special enemy in the ghost of masking often point out a swamp of contradictory information from the beginning of the pandemic. Yes, Anthony Fauci advised notoriously against masking.Yes, World Health Organization Rejected Support it for months.

But that was another time. To navigate a pandemic wisely, you need to combine healthy skepticism with the willingness to change your mind when high-quality evidence is presented. Based on the results of this and other observational studies, we need to be more confident in our dissertation on facial coverings. The use of surgical masks throughout the community clearly reduces the spread of coronavirus, especially in unventilated indoor environments. Spreads most efficiently.