Wearing vigilant masks could have prevented nearly 140 people from contracting the coronavirus at a hair salon in Missouri, according to a report released Tuesday by the Centers for Disease Control and Prevention. In May, people interacted with two stylists with confirmed coronavirus infections, but neither ended up exhibiting symptoms of COVID-19.
The team behind the study, which includes members of the Missouri Springfield-Greene County Health Department, can’t be sure of all the factors that helped prevent what might otherwise have been a disastrous outbreak. But the policies that instruct locals to cover their mouths and noses, implemented by the city of Springfield and by the salon where stylists worked, Great Clips, appear to have played an important role in fighting the spread of the disease.
“This really shows the power of facial coatings, especially indoors,” said Nadia Abuelezam, an infectious disease epidemiologist at Boston College who was not involved in the study.
The findings reiterate what scientists have been saying for months: face masks are an essential part of the disease prevention toolkit, said Juan Gutierrez, a mathematical biologist at the University of Texas at San Antonio, who models the transmission of the coronavirus. but did not participate in the study. “If we consistently deliver that message to people, we could contain it.”
Both stylists fell ill in mid-May. But they continued to work with clients for about a week after they started feeling symptoms, said Kendra Findley, a researcher with the Springfield-Greene County Health Department and author of the study.
At the time, Springfield businesses had just begun to reopen and the numbers of confirmed coronavirus cases in the region were extremely low, said Dr. Robin Trotman, an infectious disease physician and author of the study.
“There were days when we had one or two cases, maximum,” he said. Such a low local prevalence may have been part of the reason the first stylist attributed her cough and fever to allergies and kept going back to work, Findley said. Against the recommendations, she returned to her job even while waiting for the results of her coronavirus test, which she received two days after taking her test.
The second Great Clips employee fell ill within days of her colleague, although none of the other four staff stylists ended up feeling unwell. The two sick stylists eventually tested positive for the coronavirus, after which the salon told them to isolate themselves at home.
At the time, however, the couple had come into close contact with 139 clients looking for haircuts, facial hair clippings, and perms, appointments that bring people inches to each other for 15 to 45 minutes at a time, time more than enough for the virus. travel through the air from person to person.
And maybe he would have, if it hadn’t been for the masks.
In the days that followed, health officials contacted the 139 people exposed to the stylists by contact and asked them to quarantine them for two weeks. None reported feeling sick during the 14 days that followed their appointments in the classroom. The researchers also offered clients free diagnostic tests for the coronavirus. Sixty-seven of them accepted; the rest declined. Of those evaluated, all were negative.
“It surprised me,” Findley said.
Follow-up interviews with 104 of the clients revealed that, according to the guidelines, clients and stylists had worn masks during almost every encounter documented by the study.
A small handful of customers had donned N95 respirators, devices designed to filter 95% of particulates in the air and one of the best forms of protection for healthcare workers. Since the start of the pandemic, N95s have been very rare.
But most of the people in the studio, including the two stylists, opted for fabric coverings or surgical masks, baggy accessories that don’t form an airtight seal around the face.
These products are imperfect. But several studies, including some started long before the start of the pandemic, have pointed out its usefulness in hampering the spread of the virus from the user’s airways, said Julian Tang, a virologist at the University of Leicester who was not involved in the study. an email. To a lesser extent, they can also protect a user from incoming dew.
In this case, even homemade masks that can’t reliably remove all virus-laden particles appear to be the trick, an incredibly encouraging finding, Gutierrez said. “If they hadn’t been wearing those masks, we would have expected a totally different situation,” he said.
Of course, masks alone cannot be considered an infallible “safety net”, said Saskia Popescu, an epidemiologist at the hospital and an infectious disease expert in Arizona who was not involved in the study. “This is not an excuse to let yourself go and do whatever you want, especially if you’re symptomatic. “
Even the sponsors of this particular salon may not have gone without Scots. For example, some of the clients who were not tested may have harbored the virus in the absence of symptoms. And diagnostic tests, which look for genetic material from coronaviruses, may be faulty. The study also did not contact any clients with whom the stylists had interacted before feeling ill, a period during which the virus can still be transmitted to others.
Abuelezam also cautioned that the results of the Springfield Great Clips incident would not necessarily be valid in other circumstances. “It’s about short-term, indoor exposure,” he said. “We cannot generalize these results to a situation where people are together for long periods of time.”
A hint of that may even come from the behaviors of the first stylist – chances are she passed the infection on to the second Great Clips employee inadvertently during several unmasked encounters, Findley said. (He may also have transmitted the virus to three family members, presumably also without a mask.)
Even with some protection, coworkers who spend much of their day together may have a hard time minimizing transmission, Popescu said.
As discussions of the exhibition continue, he added: “We cannot focus only on the employee, the client, or the patient, the health worker, or the teacher, the student. We also have to discuss what happens among the employees. “
Still, “I hope this encourages people to take the masks more seriously,” said Abuelezam. “Clearly, they have a purpose.”
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