Just as Israelis are discarding face masks in increasing numbers, evidence of their effectiveness is growing and the World Health Organization is changing its advice to encourage their use.
Results are in for the world’s biggest study on face coverings to defend against the novel coronavirus — and they point to a major reduction in risk.
Wearing face coverings cuts chances of COVID-19 infection by 85 percent upon encountering someone with the virus, according to a Canadian-led team that published a meta-analysis of worldwide mask research in The Lancet, a peer-reviewed medical journal, earlier this month.
Israel is experiencing a spike in coronavirus cases, and the government on Monday evening said there were 179 new infections confirmed over the preceding 24 hours. Prime Minister Benjamin Netanyahu has pulled “the emergency brake” on further easing the virus restrictions.
On Sunday, Netanyahu rebuked the nation for reduced adherence to precautions, including face coverings. Addressing the cabinet, he said that part of the recent spike in cases is a result of opening up the country “but some of it also clearly stems from a loosening in strict adherence to the rules regarding masks, distancing and hygiene.” Israel has seen nearly 300 deaths from the virus, and currently has nearly 3,000 active infections.
The World Health Organization-funded team that published its findings in The Lancet found that healthy people who are around an infected person reduce their chances of catching coronavirus from 17.4% to 3.1%, by wearing a mask. Staying a meter (3 feet) or more apart reduces infection rates from 12.8% to 2.6% — and social distancing becomes even more effective as the distance increases to two or three meters.
While health authorities around the world were quick to call for social distancing during the pandemic, many have been more hesitant about asking people to wear masks. The WHO initially said there was no evidence to support asking healthy people to wear masks. But over the last few days, since the new study was released, it has changed its position, and now encourages the use of masks in many public settings. The WHO currently takes the view that masks can be “a barrier for potentially infectious droplets.”
‘Masks do actually save lives’
In Israel, the public was told to wear masks in public on April 1, earlier than in many other countries, and their use was then enshrined in law, but officials say that many people are now failing to follow the instruction. Some experts say the new study could be just what they need in their uphill struggle to convince people to wear masks and observe social distancing.
“It’s an objective scientific demonstration that masks do actually save lives,” immunologist Cyrille Cohen told The Times of Israel. “It’s important because it backs up with statistics what we thought and believed to be correct.”
Cohen, head of the immunotherapy laboratory at Bar-Ilan University, added: “The conclusion is that wearing masks can limit infection and contamination, and this is very important when we’re in a period after confinement, when people are going out, and when you see in streets of Israel people often aren’t wearing masks.”
Immune system expert Tomer Hertz said the new study helps challenge a common perception about masks. “This shows that masks are good for protecting the person wearing them, and not just for protecting others,” he said.
Hertz, a member of faculty at Ben-Gurion University of the Negev’s Microbiology, Immunology and Genetics, added: “The study shows that masks are a good long-term strategy for the public.”
The Lancet study comes as another journal retracted a paper that had cast doubt on the usefulness of masks.
A month ago, Annals of Internal Medicine published an article claiming that masks worn by infected people don’t stop them transmitting COVID-19 when they cough. Masks “seem to be ineffective in preventing the dissemination of SARS–CoV-2 from the coughs of patients,” wrote a team from University of Ulsan, South Korea. Last Tuesday the researchers wrote that editors had asked them to retract their article, and admitted that their results were “uninterpretable.”
The Lancet research, led by Derek Chu of Canada’s McMaster University, was a meta-analysis of some 172 studies that have been conducted in 16 countries and six continents tracking the health of people who followed recommended practices. They focused on COVID-19, and other infections caused by the same family of viruses: severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS).
Around a third of the studies tracked people who didn’t take precautions as well as those who did, for the sake of comparison. The authors believe theirs is the first paper to “rapidly synthesize all direct information on COVID-19” and therefore “provide the best available evidence” on interventions to fight the virus.
They highlighted the danger of infection via eyes, suggesting that eye protection isn’t used enough. They wrote that infection can occur both when people touch their eyes and when droplets from a COVID-19-positive person reach the eyes of another through the air.
“Eye protection is typically under-considered and can be effective in community settings,” they wrote, reporting that healthy people encountering a person ill with the coronavirus can cut the chance of infection from 16% to 5.5% by adding eye protection.
The Lancet study also looked at different kinds of masks, and concluded that disposables masks are more effective than the now-fashionable fabric masks, normally made from a single layer. “Both N95 and surgical masks have a stronger association with protection compared with single-layer masks,” wrote the researchers.
Cohen, of Bar-Ilan University, said it took time during the pandemic for scientists to fully understand the power of interventions like masks.
“People said at first that the virus is so tiny so the masks won’t be effective, but we understand that it’s passed through droplets, and that the moment you’re talking about droplets they are larger than the virus alone, and physical barriers are effective,” said Cohen.