A man who smokes shisha under his mask -
JAAFAR ASHTIYEH / AFP
In his latest video, Professor Didier Raoult establishes a link between shisha and the spread of Covid-19 within a cluster that the IHU has investigated.
Even though hookah appears to promote aerosol contamination, this link remains to be scientifically proven.
Smoking shisha leads in any case to being close to each other, often without a mask, factors conducive to the spread of Covid-19.
Shisha, a new transmission factor for Covid-19?
At least that is what Professor Didier Raoult assumes in a video published Tuesday, entitled "Chicha and risk of infection, prognosis and treatment".
“We looked at what could be a new cause of transmission,” explains the director of the IHU in Marseille.
During a little investigation that we did, people told us: "You know, on Saturday night, we all went together to smoke shisha".
And to estimate: "This thing is disgusting.
If we do this thing, in which there is saliva, including if we change the mouthpiece, it's an extraordinary experimental model for transmitting respiratory disease.
"According to Professor Didier Raoult," you cannot escape the fact that you are emitting aerosols with saliva into something that is hot ".
A phenomenon which, in this logic, could even explain a resumption of the epidemic among young people last summer.
“These infectious diseases are always linked to a new technology or to a change in the ecosystem,” says the director of the IHU.
And this thing, to go from mouth to mouth, that did not exist before.
, the IHU specifies that these declarations were made after an investigation into a specific source of contamination.
"We have been alerted to a cluster in the workplace," explains one to the IHU.
The teams first asked themselves questions about the working conditions of the people concerned, if there were ventilation problems where they worked.
And it turned out that they had, at a party, smoked shisha together.
And to add: “There are questions around the transmission.
We put the mouthpiece in the mouth.
Shisha is hot, humid.
Under these conditions, the virus can spread very easily.
A short article on the subject published in the
Canadian Medical Association Journal
on April 6, 2020 states that “shisha is an ideal model of transmission and can, through its shared use, exacerbate the risk regarding Covid-19.
"The shisha involves breathing more deeply, blowing away from the smoke," notes Simon Mendez, researcher at the CNRS and at the Alexander Grothendieck Institute in Montpellier, specializing in fluid mechanics.
These are all elements which a priori increase the quantity of droplets in the room, which increases the risks compared to a more standard situation.
"And to recall:" We have more and more suspicions about aerosol contamination.
The tiny droplets stay suspended in the air, and it is enough if they are inhaled in a poorly ventilated room for this to be a cluster factor.
The researcher is however cautious.
"We do not know if inhaling smoke is a factor of contamination with Covid-19".
No scientific study on the subject has in fact been carried out to date.
"It is recognized that being in close proximity without a mask is a moment of contamination," recalls Jean-Stéphane Dhersin, scientific deputy director of the National Institute of Mathematical Sciences and their Interactions, specializing in the modeling of epidemics.
We can cite canteens, bars… Festive moments, without a mask, are vectors of transmission of the virus, as several French and foreign studies show.
And to assert: “For this cluster, they smoked shisha at a party, but we must not confuse correlation and causality.
It is not necessarily because they smoked the shisha that they were contaminated.
It was above all a gathering of several close people.
The IHU says it plans to work quickly on the subject to support this thesis.
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