The risk of catching the COVID-19 decreases to 80 % when there is at least one metre in distance from others and still falling by half when we stick to a distance of two metres, according to a major canadian study.
According to the study published Monday in the journal The Lancet and funded by the world health Organization (WHO), the risk of being infected is, on average, from 12.8% to near a person infected by the COVID-19 if you do not abide by the rules of social distancing.
Maintain a distance of a meter or more, this risk drops to 2.6 %, a relative decline of 80 %. In addition, for each meter of distance additional, the risk of transmission would reduce by half.
These results have been obtained as the result of a major review of scientific, which identified 172 studies from 16 countries published in the last several years about three respiratory infections : the COVID-19, but also the SARS and MERS, the latter two being the oldest and therefore the best documented.
“Broad protection “
This meta-analysis also found that wearing a mask and eye protection greatly reduces the risk of transmission of the virus.
In this sea of data, nine studies were used to the results for the distance physical.
“Our main conclusion is that a separation physical of approximately a meter or more provides probably a broad protection against infection,” says the lead author of the article and a professor at the university of ontario McMaster, Holger Schünemann, in an interview with The Journal.
Photo courtoisieHolger Schünemann
These results feed the debate on the distancing of the physical places in the world where it is two meters (except between members of the same household), as is the case in Quebec.
Several countries and WHO are content, however, recommend a distance of at least one meter.
Mr. Schünemann does not want to settle this debate, but his work does not contradict the rule of two meters. On the contrary, “the available evidence suggests that both metres could be more effective than a metre,” he says.
Question of context
The scientist says that everything is a matter of context and that it should not be assumed that the estimates of his team apply to all situations.
Factors such as the location (open or closed), the exposure time or the viral load received are vary greatly the risk of contracting the COVID-19 of another person.
Invited to comment on this study, the epidemiologist, quebec Caroline Quach-Thanh is of the opinion that it is necessary to continue to promote two metres in Quebec. “When we said two metres, it is well known that people under-evaluate all the time, so we tend to pick them up at a metre, a metre and a half. The goal of aim two meters is that the risk is actually twice as big, ” she noted.
For unequal rules in the world
► At least 2 m :
- United States
- United Kingdom
► At least 1.5 m :
► At least 1 m :
In schools, the rules of social distancing are generally the same as in the society and, therefore, varies also from one country to the other.