Surgical masks reduce COVID-19 spread
A large, randomized trial led by researchers at Stanford Medicine and Yale University has found that wearing a surgical face mask over the mouth and nose is an effective way to reduce the occurrence of COVID-19 in community settings.To get more news about famous medical mask factory outlet, you can visit tnkme.com official website.
It also showed that relatively low-cost, targeted interventions to promote mask-wearing can significantly increase the use of face coverings in rural, low-income countries. Based on the results, the interventional model is being scaled up to reach tens of millions of people in Southeast Asia and Latin America over the next few months.
The findings were released Sept. 1 on the Innovations for Poverty Action website, prior to their publication in a scientific journal, because the information is considered of pressing importance for public health as the pandemic worsens in many parts of the world.
“We now have evidence from a randomized, controlled trial that mask promotion increases the use of face coverings and prevents the spread of COVID-19,” said Stephen Luby, MD, professor of medicine at Stanford. “This is the gold standard for evaluating public health interventions. Importantly, this approach was designed be scalable in lower- and middle-income countries struggling to get or distribute vaccines against the virus.”
Luby shares senior authorship with Ahmed Mushfiq Mobarak, PhD, professor of economics at Yale, of a paper describing the research. The lead authors are Ashley Styczynski, MD, MPH, an infectious disease fellow at Stanford; Jason Abaluck, PhD, professor of economics at Yale; and Laura Kwong, PhD, a former postdoctoral scholar at Stanford who is now an assistant professor of environmental health sciences at the University of California-Berkeley.
The researchers enrolled nearly 350,000 people from 600 villages in rural Bangladesh. Those living in villages randomly assigned to a series of interventions promoting the use of surgical masks were about 11% less likely than those living in control villages to develop COVID-19, which is caused by infection with the SARS-CoV-2 virus, during the eight-week study period. The protective effect increased to nearly 35% for people over 60 years old.
Providing free masks, informing people about the importance of covering both the mouth and nose, reminding people in-person when they were unmasked in public, and role-modeling by community leaders tripled regular mask usage compared with control villages that received no interventions, the researchers found.
In the intervention villages, they also saw a slight increase in physical distancing in public spaces, such as marketplaces. This finding indicates that mask-wearing doesn’t give a false sense of security that leads to risk-taking behaviors — a concern cited by the World Health Organization during the early days of the pandemic when its officials were considering whether to recommend universal masking.
“Our study is the first randomized controlled trial exploring whether facial masking prevents COVID-19 transmission at the community level,” Styczynski said. “It’s notable that even though fewer than 50% of the people in the intervention villages wore masks in public places, we still saw a significant risk reduction in symptomatic COVID-19 in these communities, particularly in elderly, more vulnerable people.”
Cloth vs. surgical masks
There were significantly fewer COVID-19 cases in villages with surgical masks compared with the control villages. (Although there were also fewer COVID-19 cases in villages with cloth masks as compared to control villages, the difference was not statistically significant.) This aligns with lab tests showing that surgical masks have better filtration than cloth masks. However, cloth masks did reduce the overall likelihood of experiencing symptoms of respiratory illness during the study period.
Bangladesh is a densely populated country in South Asia. It was chosen as the site of the trial for several reasons: One, mask promotion is considered vital in countries where physical distancing can be difficult; two, Innovations for Poverty Action Bangladesh had already established a research framework in the country; and three, many local partners were eager to support a randomized, controlled trial of masking.
“We saw an opportunity to better understand the effect of masks, which can be a very important way for people in low-resource areas to protect themselves while they wait for vaccines,” Kwong said. “So we collaborated with behavioral scientists, economists, public health experts and religious figures to design ways to promote mask use at a community level.”
Despite a growing body of scientific evidence that masks reduce the spread of the virus that causes COVID-19, it has been difficult to increase mask-wearing, particularly in low-resource countries and among people living in remote or rural areas. In June of 2020, only one-fifth of Bangladeshis in public areas were wearing a mask that properly covered the mouth and nose despite a nationwide mask mandate that was in effect at the time.