Brazilian researchers have questioned whether the increase in temperatures in a humid subtropical climate is correlated with a reduction in the number of cases of contamination. The answer seems to be positive but has nuances.
No, contrary to the words of a certain American president, the COVID-19 coronavirus and the pandemic it is causing will not magically disappear with the heyday. Brazilian researchers have nevertheless asked themselves the question in a scientific manner: and if the heat brought by the Sun Could affect the survival of SARS-CoV-2 coronavirus and thus reduce the number of infections? To answer this, they compared the meteorological and temperature readings to the numbers of patients recorded daily in 27 major cities in Brazil, from February 27 to April 1. In this subtropical country of South America, this time of the year remains very sunny and thus has average temperatures between 16.8 and 27.4 degrees Celsius. As they detail in their study published in the journal Science of the Total Environment, the researchers noticeda linear trend that shows a reduction in the number of cases with increasing temperatures.
Indeed, each increase of one degree would correspond to a drop of around 5% in the number of cases recorded per day. This apparently relative decrease in increasing heat applies up to a limit of 25.8 ° C. Beyond this level, the number of cases starts slightly up again before stabilizing. However, researchers are unable to explain this relationship between increasing heat, humidity and survival of the virus biologically. “Our findings do not show that the COVID-19 coronavirus disappears by itself when the local climate warms up”, admit the researchers at the conclusion of their study. “The social distancing measures in force could very well have had a direct impact on the evolution of the number of infections and therefore the results of our research. ” In other words, if the virus can effectively withstand a certain dose of heat, it is especially undermined by the strictest limitation of its spread and respect for barrier gestures, dedicated to reducing the risk of contamination. The Sun and its heat can nevertheless lend a hand to these essential methods. In addition to rising temperatures, increased solar radiation in summer can also help exterminate the virus on surfaces, especially outdoors. Indeed, as the scientific journal Science explained last March, extensive exposure to the sun’s ultraviolet rays would be enough to exterminate it if necessary – as is the case for most microorganisms. On the other hand, one should not mistakenly believe that UV rays can protect our body from infection or transmission of the virus. As the ARC Foundation for Cancer Research recalls, ultraviolet radiation is harmful to our body and can cause skin cancer. This summer, as every year, sunscreen is therefore essential!
–
