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Stanford, Yale Study Shows Wearing A Mask Significantly Drops Covid-19 Spread

A large scale study from Stanford shows masks do work. Stanford researcher Dr. Ashley Styczynski spoke with KPIX about the results of the study.

"We took we took 600 villages across Bangladesh enrolling nearly 350,000 adults. And half of them were assigned to our mass promotion intervention," said Stanford Researcher Dr. Ashley Styczynski. "And within this, we included many different types of promotion activities from text messaging reminders, to public signage about the importance of wearing masks."

"We were able to observe that we had a 29% point increase in the villages that received this intervention. So that was significant. It was actually a tripling from the baseline that we saw."

"The second part of the intervention then was to measure what effect this had on COVID-19. And we did this by asking the participants over the course of the study, if they had any symptoms, such as symptoms consistent with COVID-19 respiratory symptoms, gastrointestinal symptoms, and those who had symptoms that were consistent with COVID-19."

"We then collected their blood at the end of the study, and we tested it for antibodies against the SARS CoV 2 virus. And what we found from this was that with a 29 % point increase in mass squaring, we were able to reduce COVID-19 cases by 9%."

"And this effect was primarily driven by the surgical masks. When we looked at just the surgical mask by themselves, we found that they were 11% effective at reducing COVID-19 cases. And furthermore, when we stratify this by different age groups, we found that there was an increasing effect with increasing age.  So for people aged 60 and above, we actually were able to reduce 35% of COVID-19 cases, which was pretty remarkable considering that this is such a high risk group."

"Certainly rural Bangladesh is not the same as the Bay Area. There are many, many differences. But I think if anything, that the Bay area stands to see even more benefit from mask wearing. And the reason for this is because we spend a lot more time indoors than people do in rural Bangladesh who are primarily outdoors and a very well-ventilated spaces."

"And so in the Bay Area, as we transition back into offices, back into schools, we're going to be in higher risk environments where people are going to be in closer proximity. There may be re-circulated air. We may not have the option to open windows for example. And so we really do need to think about how we can make this transition as safe as possible."

"And so I think masks are going to be a really key strategy as a part of that. Even in groups of people that are highly vaccinated, uh, especially thinking about places where people may not be fully vaccinated, um, is even more imperative that we use this as a strategy. "

"So for example, in schools where most of the children are ineligible for the virus But also in places of work where there may be other employees who they're unable to receive the vaccine or the vaccine may not be as effective. And thinking about how to protect the community at large as a real strategy to reduce the overall transmission of the virus."

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