COVID-19.Are school masks useful?newsletter

The government announced this on Wednesday September 22 at the end of the Council of Ministers.From October 4, and in the departments where the incidence rate stabilizes below the threshold of 50 per 100,000 inhabitants, "the health protocol will pass at level 1, which essentially means that the obligation to portMask in primary school will be lifted ».A decision that is debated and which aroused numerous reactions from scientists who fear a resumption of the COVVI-19 epidemic.

What do the latest studies conducted on the subject say?In the United States, where the start of the school year has spread between mid-July and mid-August according to states, the results of two new research on the issue was published last night, Friday September 24, by centers for controland disease prevention (CDC)) and relayed by Leparisien.

More risks of clusters

The first which studied the situation in a thousand schools of two counties of Arizona, reveals that those not demanding the wearing of the mask are 3.5 times more likely to create a cluster.To arrive at this result, the researchers divided establishments into three groups: those where facial protection was imposed as soon as the school year and staff (210 in total)), those who decided later (309 schools)) and those where the mask was not compulsory (480 schools)).

To achieve this probability, they counted in each of the situations the number of departure of epidemic in schools.Thus on the 191 clusters or beginnings of clusters noted (from two cases of contamination)), they counted 16 in establishments imposing the mask since the start of the school year, 62 in those which adopted it later, and 113 which n'never imposed this measurement.

Stronger incidence rates without mask

The second study has looked at the incidence rate according to the measures taken in schools, during the two weeks following the start of the school year.Again, the results argue in favor of wearing the mask.This research this time focused on 520 American counties where the same rules were essential and not on schools.

The authors wanted to verify whether the incidence rate in students varied according to the obligation (or not)) of the port of the mask at the school.Assessment: the number of cases of COVID-19 in children increased everywhere after the start of the school year but even more in the counties where the masks were not compulsory: nearly 35 cases per 100,000 inhabitants against 16 per 100,000 incounties where children were masked.To reach these rates, scientists have adjusted their data taking into account several other factors in the various counties: children of children, population densities or the vaccination rate or social data on the population (percentage of insured,etc.)).

Results to take with care

If they consolidate the arguments of American health agencies in favor of maintaining the mask in schools, these two American studies are not truly transposable to the French case.For several reasons.On the one hand, because they relate to American schools in the broad sense ("schools")).They include establishments up to grade 12 of the American education system, primary schools but also colleges and high schools.

However in France, the decision to lift the port of the mask only concerns primary schools.As a reminder, the mask is currently compulsory from CP in primary schools, from the age of 6.And last June, the measure had already been softened, allowing children to remove the mask outdoors, in the playground.

The second study also presents several limits, indicate the researchers.For them, the absence of obligation to carry the mask cannot be considered as the only cause of the epidemic recovery in certain establishments.Even if, the authors of the study submitted their results to several other variables, for example they have not taken into account the vaccination rate of teachers.On the other hand, in some counties, the samples were too small to make it a generality.

Fewer closed classes

Finally, the American epidemic recovery in schools can hardly be a case of school for France, because in our country, the start of the school year has so far rhymed with flambée cases of COVID-19 as some specialists fearedthe start of the school year.According to the Ministry of Education, the number of classes closed due to the epidemic is even in sharp decline.The Ministry of National Education announced that 2,366 classes were closed Thursday, September 23, or nearly 1,000 less classes compared to last week.