A practice of widespread wearing of facemasks in public, combined with lockdowns, could prevent future waves of COVID-19. That's according to new research unveiled Wednesday led by Cambridge and Greenwich universities in Britain. And the more people who get on board, the less restrictive those lockdowns may need to be.
"The research suggests that lockdowns alone will not stop the resurgence of SARS-CoV-2, and that even homemade masks with limited effectiveness can dramatically reduce transmission rates if worn by enough people, regardless of whether they show symptoms," Cambridge said in a statement summarizing the study.
The authors say widespread mask use would help buy time until a working vaccine can be found.
The key to the study is the "R" number. That's the number of people a person infected with the coronavirus passes the virus onto. Researchers say that number needs to stay below 1.0 for the pandemic to slow.
The study concluded that when people wear masks in public, it is twice as effective at reducing the "R" than if masks are only worn when someone shows symptoms. One model showed that even just 50% of the population wearing masks can reduce the "R" to below 1.0. That can result in less-restrictive lockdowns.
“We have little to lose from the widespread adoption of facemasks, but the gains could be significant," said study co-author Dr. Renata Retkute of Cambridge.
Experts have said that homemade or cloth masks do little to protect a healthy wearer from catching the virus, but it can help prevent someone who has COVID-19 from spreading it to others. This study specifically cites research that found homemade cloth masks can be 90% effective at preventing transmission.
“Cultural and even political issues may stop people wearing facemasks, so the message needs to be clear: my mask protects you, your mask protects me," professor John Colvin, a study co-author from Greenwich, said in a statement.
The study concluded that such practices can work in both developed and developing countries, the latter of which may need to rely more on homemade masks than medical-grade ones.
The study is published in the journal Proceedings of the Royal Society A.
The World Health Organization last Friday updated its guidance, recommending everyone wear face masks in public in regions where the disease is spreading.
For most people, the new coronavirus causes mild or moderate symptoms, such as fever and cough that clear up in two to three weeks. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia and death. The vast majority of people recover.
The Associated Press contributed to this report.