WASHINGTON — President Trump on Friday announced new federal guidance that encourages Americans to use homemade cloth face coverings when in public, a new effort intended to slow the spread of the novel coronavirus.
The guidance reflects a growing concern that individuals who don’t display coronavirus symptoms could still unknowingly transmit the disease while in public. Trump’s announcement matches a draft recommendation the Centers for Disease Control and Prevention formulated Thursday, which urges Americans to use the cloth face coverings during trips to the grocery store and other public outings. The guidance, according to the CDC document, is intended not to guard the wearer but instead to prevent the wearer from unknowingly transmitting the virus to others.
“The CDC is recommending that Americans wear a basic cloth or fabric mask that can be either purchased online or simply made at home, probably [with] material that you’d have at home,” Trump said during a press briefing at the White House.
The president emphasized that the guidance does not call for Americans to use surgical masks or N95 respirator masks, which officials hope to preserve for medical professionals and hospitals amid severe shortages in personal protective equipment.
Trump also stressed that the new recommendation on face coverings does not replace existing guidelines that urge Americans to stay home as much as possible, avoid social gatherings, and maintain 6 feet of distance between other people at all times. Deborah Birx, the physician helping to coordinate the Trump administration’s coronavirus response, expressed a similar concern on Thursday, arguing that widespread use of face coverings might lull some Americans into a false sense of security and cause many individuals to take social distancing measures less seriously.
Trump, however, downplayed the recommendation.
“This is voluntary,” Trump said. “I don’t think I’m going to be doing it.”
The announcement comes as the coronavirus and Covid-19, the respiratory disease it causes, continue to spread through American cities. Early research shows that individuals who are infected with the coronavirus but haven’t yet displayed symptoms can still spread the virus. Public health experts hope that by using masks when venturing outside for grocery runs and other essential trips, individuals might be less likely to unknowingly transmit the virus.
Such approaches have shown early success in some Asian countries that appear to have succeeded in beating back the virus, including Japan, Singapore, and South Korea. Those countries’ approaches have relied largely on basic public health interventions including social distancing, widespread testing, isolating confirmed cases, and following and quarantining their contacts. But the general use of masks in some of those countries has also led to speculation that the masks helped bring the initial outbreaks under control.
Fearful of further straining an already limited supply, experts on all sides of the debate have stressed that the most protective of masks, like N95 respirators, be reserved for frontline health care workers. But from there, experts have disagreed whether everyday use of cloth masks or other forms of mouth and nose coverings are beneficial.
The World Health Organization has recommended that people who are sick, and those caring for them, wear masks. WHO officials have said that masks are only shown to be effective as a tool to block the spread from people who are infected to others, rather than a preventive tool for people who are not infected.
“The evidence is quite clear that the wearing of a mask in public doesn’t necessarily protect you,” Mike Ryan, the head of the WHO emergencies program, said during a Friday press briefing. “But if a sick person wears a mask, then it is less likely they may infect others. At the moment, and from a WHO perspective, people who are sick with Covid-19 should be in isolation.”
A new study published Friday in the journal Nature Medicine provided further evidence for mask wearing by people who are sick. Researchers at the University of Hong Kong found that surgical masks reduced the levels of some viruses — including influenza and the coronaviruses that cause the common cold — that were emitted by people compared to people who were not wearing them. The study did not include SARS-CoV-2, and it found that masks did not reduce the projection of rhinoviruses.
As evidence has mounted that people without symptoms can still transmit the coronavirus, some experts have called for the general public to wear masks as a preventive measure. WHO officials on Friday acknowledged the debate is ongoing, and the question is being studied. Ryan said the WHO will support governments as they make recommendations about masks.
But he added that such decisions need to be made in the context of the available resources and the level of spread in a community. He characterized homemade or cloth face coverings as one tool in a broader, more comprehensive strategy.
“That doesn’t negate the need for hand washing, it doesn’t negate the need for physical distancing, it doesn’t negate the need for people to stay at home if there’s a stay-at-home order in place, it doesn’t negate the need for everyone to protect themselves and to try to protect others,” Ryan said.