Wearing of masks prevented outbreak at US hair salon: CDC

WASHINGTON • Two US hair stylists who wore masks while infected with the coronavirus did not pass it on to the nearly 140 clients they saw over the course of several days, a study said on Tuesday.

The report, released by the United States Centres for Disease Control and Prevention (CDC), said the findings added weight to universal face covering policies as a means of slowing the spread of the virus.

On May 12, a hair stylist (Stylist A) developed respiratory symptoms at a salon in Springfield, Missouri, and continued working with clients until May 20, when she received a positive test for the coronavirus.

Stylist A ignored medical advice to self-isolate after her test on May 18.

A second hair stylist (Stylist B), who had been exposed to the first, developed symptoms on May 15 and also continued working until May 20, when Stylist A got her test result. Stylist B tested positive two days later.

Health officials performed contact tracing, identifying a total of 139 clients seen by the two stylists.

The rest of the salon's staff were also quarantined for two weeks.

During their interactions with clients, both stylists had worn masks: Stylist A had worn a double-layered cotton face covering, while Stylist B had worn either a double-layered cotton face covering or a surgical mask.

But even when Stylist A had symptoms, the two stylists interacted with each other while neither was masked, in intervals between clients.

All 139 clients were monitored for symptoms for the next two weeks, and testing was offered to all of them.

None of the 67 tested was found to be positive, and none of those who refused testing reported symptoms over the next 14 days when they were sent daily text messages inquiring about their health.

The overwhelming majority wore either cloth masks or surgical masks for the entire duration of their appointments, which ranged between 15 minutes and 45 minutes.

Scientists believe that while large droplets emitted by coughing or sneezing are primarily responsible for spreading Covid-19, smaller droplets released during ordinary speech are also potentially dangerous.

This is particularly important because people might spread the virus unknowingly before they develop symptoms, or in rare cases, when they do not develop symptoms at all.

The authors of the CDC report concluded with a call for "widespread adoption of policies requiring face coverings in public settings" to reduce the scale and impact of Covid-19.

In an online interview with the Journal of the American Medical Association, CDC director Robert Redfield said that if all Americans wore a mask, the rising cases of Covid-19 could be under control within four to eight weeks.

But he also said he was "sad" that the issue had become so politicised.

"I am glad to see the President and Vice-President wear a mask. Clearly, in their situation, they could easily justify they don't need to... but we need for them to set the example."

AGENCE FRANCE-PRESSE, REUTERS