(Washington) Scientists in the United States government believe that the new coronavirus is most likely transmitted by people when they speak and breathe. Logical consequence: Americans are now officially advised to cover their faces outside their homes, to help curb contagions.
France Media Agency
President Donald Trump announced it on Friday evening, stressing that it was a non-binding recommendation. The health authorities call on the population to cover their faces with handmade masks, scarves or bandanas, in order to reserve medical masks for carers, a shortage requires.
This decision by the Centers for Disease Control and Prevention (CDC), the national health authority in the United States, is “only a recommendation,” Trump said in a press briefing.
“It's (initiative) voluntary,” he insisted. “Personally, I will not wear one,” he continued.
“Sitting in the Oval office […] Wearing a mask while receiving presidents, prime ministers, dictators, kings, queens, I don't know, I don't feel it for me”, a he said again.
The CDC insists in particular on the need to cover your face while shopping, when the recommendations for social distancing are more difficult to comply with.
In New York, the mayor had already asked residents to cover their faces outside their homes, and as of Friday, just under half of the pedestrians were applying the order in Manhattan, according to an observation by journalists from AFP.
Seen from Asia, where surgical masks are omnipresent, the delay in Western countries is an aberration. But health officials in the United States or France, as well as the World Health Organization, have so far argued that the mask is not necessary for healthy people unless they are in contact with the sick.
For several days, a flip-flop has been preparing, under pressure from an audience that does not understand why the masks would protect nurses, but not ordinary citizens.
In France, the French Academy of Medicine recommended the compulsory wearing of a mask on Friday as a “logical addition to the barrier measures”.
In the United States, on Friday, the director of the Institute of Infectious Diseases, Anthony Fauci, member of the White House working group on the coronavirus who says he spends an hour a day with President Trump, Fox Data reported that “the virus can actually be transmitted when people are just talking, rather than just when they sneeze or cough.”
Transmission by air would provide a long-sought explanation for the apparent high contagiousness of the virus responsible for the COVID pandemic – 19, since it appears that infected people, but without symptoms, which represent perhaps a quarter of all infected people, are responsible for a large part of the contagions, without their knowledge.
Multiple studies have shown that asymptomatic people had infected people close to them in churches, in a choir or a singing class, in retirement homes …
What is the scientific evidence? There are few, but they converge.
The American Academies of Sciences cited in a letter to the White House Wednesday four studies tipping the balance in favor of transmission of the virus via the air exhaled by people (“aerosols” in scientific jargon), and no longer only by the droplets and postlets projected during a sneeze directly on the face of other people or on surfaces (where the virus can survive for hours or even days, depending on the type of surface ).
“The research currently available supports the possibility that SARS-CoV-2 can be transmitted by bioaerosols generated directly by the exhalation of patients”, writes Harvey Fineberg, president of the committee on emerging infectious diseases .
He emphasizes that more is needed to better understand the real risk of infection. If the virus is actually present in respiration, it is not known whether this represents a significant route of transmission quantitatively.
In a study, researchers from the University of Nebraska found portions of the virus’s genetic code (RNA) in the air of rooms where patients were isolated.
Researchers at the University of Hong Kong recently observed that wearing masks reduced the amount of coronavirus exhaled by patients (the experiment was done with viruses other than SARS-CoV-2).
And researchers in Wuhan took air samples from various hospital rooms and found high concentrations of the new coronavirus, especially in the toilets and rooms where caregivers removed their protective gear.