Vaccinated Americans must once again wear the mask indoors in high-risk areas, the country's health authorities (CDC) said on Tuesday.
"In areas where transmission (of Covid-19) is high, the CDC recommends that fully vaccinated people wear masks in public places indoors," said Rochelle Walensky, director of the Centers for the Prevention and Control of diseases.
The rumor had been circulating for a few days: the main health officials of the country met Sunday evening to discuss the subject, according to CNN. Yet last week, the CDC was still pushing for the idea that people vaccinated do not need to wear the mask indoors. But the rapid spread of the Delta variant in the United States, where it represents 90% of contaminations, made this new directive necessary.
Another observation: if the current vaccines remain very effective against the serious forms of the disease, hospitalizations and deaths, one observes more and more cases in the vaccinated people.
New data “indicate that on rare occasions, people who have been vaccinated (…) could be contagious and transmit the virus to others.
These new findings are worrying and unfortunately justify an update of our recommendation.
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According to CDC figures, the number of infections is on the rise in much of the southern United States, but less in the Northeast, which is better vaccinated.
To curb the spread of the Delta variant, the CDC will also recommend that schools ask teachers, students or visitors to wear the mask, whether or not they are vaccinated.
1,000 times greater Delta variant viral load
A study published recently in the scientific journal Virological shows that the viral load in the first tests of patients affected by the Delta variant was 1,000 times greater than that of patients in the first wave of the virus in 2020.
Not only does the Delta variant reproduce within its host faster than previous strains, infected people spread the virus much more in the air, greatly increasing the likelihood of transmission.
“This does not mean that the quality or level of protection of the vaccine has declined,” says Eric Cioe-Pena, public health expert at Northwell Health.
It is a solution to a problem that exists because we have a high level of people who are not vaccinated.
Last month, Israel reinstated some mask-wearing requirements, just 10 days after lifting them, in light of the spread of the Delta variant.
Some US local authorities such as Los Angeles County have taken similar measures.