The seventh wave, which has been hitting France for several weeks, could well find an accelerator in the coming days: the heat wave. With temperatures that can reach 39°C from this Tuesday, Public Health France recommends keeping your accommodation cool and closing windows and shutters during the day. But, are these measures compatible with regular ventilation, essential in the fight against Covid-19?
Epidemiologist Dominique Costagliola warns: the heat wave could increase the circulation of the virus in closed places.
“The virus is transmitted by aerosols,” recalls the emeritus director of research at Inserm. “During a heat wave, we ventilate less. We are further in and therefore more likely to have high aerosol transmission.”
Public Health France calls in effect to “favour” the prevention of the heat wave to that of the virus. “Ventilation to combat the transmission of Covid-19 should be limited to the coolest hours, when outdoor temperatures are below indoor temperatures,” the organization recommends.
“We must wear the mask inside the house”
Under these conditions, and with more than 130,000 cases on average every day, Dominique Costagliola asks to keep the mask indoors. “You have to put your mask on inside until you have invested in air quality,” he insists. “Invest in efficient metering and ventilation systems. This is particularly important for schools and businesses, but can extend to performance venues.”
The only positive point of the period, the school holidays. “One element changes in summer: children do not have school,” says the epidemiologist. “They are a transmission vector of the epidemic. Rather we have seen positive effects of holidays, even if they occur in winter.”
The risks of air conditioning
In this period of intense heat and epidemic rebound, is air conditioning the miracle solution?
“Depending on the type of air conditioning, it can be good or bad. The essential thing is the quality of the air”, insists Dominique Costagliola.
As the World Health Organization points out, “most wall or window air conditioning systems do not provide ventilation”, “they are designed to reduce the temperature and humidity of the air, and this, by recycling the indoor air. That is, they do not do without ventilation.
The Ministry of Health has made several recommendations for the use of air conditioners, whether collective or individual. In both cases, it is recommended to “use the most efficient filters possible from a sanitary point of view, remove, periodically clean and reinstall pre-filters” and “make sure that fans and air conditioners do not generate drafts”. directed at people.
Other barrier measures
Public Health France issues other recommendations to prevent transmission of the virus during this very hot period:
- reinforce other barrier measures: hand washing, use of a mask in cooled collective places, physical distancing
- do not use fans in the presence of third parties
- self-isolate when you have symptoms or test positive
- be up-to-date with vaccination against Covid-19 in case of future episodes of intense heat
Jean-François Delfraissy, president of the Scientific Council, estimated on Monday that the health system “will hold” in the face of this seventh summer wave. “The most important thing”, according to him, “is to protect the oldest and highest risk people”, reinforcing their vaccination.
Source: BFM TV
