It's been more than three years since Covid-19 emerged, and despite the outbreak killing thousands there is not enough evidence whether wearing face masks can stop the spread of respiratory viruses. The Centers for Disease Control and Prevention initially claimed that face masks are not necessary and then in April 2020, it asked people to mask up.
In September, CDC Director Dr Robert Redfield said that face masks are the most important powerful health tool we have, Fox News reported.
Wearing face masks soon became mandatory across the world.
Now, a review led by 12 researchers from esteemed universities around the world has said that masking up may have done little to nothing to stop the transmission of Covid-19.
The review was published by Cochrane Library and researched 78 controlled trials to check whether "Physical intervention"- including face masks and hand washing curbed the spread. Cochrane Reviews are widely considered the gold standard of evidence-based medicine, the Slate report said.
The review author said, "Wearing masks in the community probably makes little or no difference." The researchers compared masking with non-masking to prevent Covid-19.
The study further claimed that there was no clear difference between medical/surgical masks versus N95. The study found that "wearing N95/P2 respirators probably makes little to no difference in how many people have confirmed flu (five studies; 8407 people); and may make little to no difference in how many people catch a flu-like illness (five studies; 8407 people), or respiratory illness (three studies; 7799 people)."
The 78 studies looked at participants from countries of all income levels, Fox News reported.
The researchers collected data during the H1N1 flu pandemic in 2009, non-epidemic flu seasons, epidemic flu seasons up to 2016 and the COVID-19 pandemic, the study authors wrote.
According to a Bloomberg report, the research conclusion isn't totally cut and dried. Some studies included in the review were done before Covid when transmission and circulation of the viruses weren't as intense. Many people didn't wear their masks faithfully. Other research shows masks can significantly reduce Covid transmission rates, especially in tight indoor environments, making them a critical tool.
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