Re: Good News Covid-19?
The news; Higher temperatures and humidity are correlated with a lower rate of the novel coronavirus’s spread, according to early research. The hypothesis is plausible: the climate’s impact on the influenza virus is well established, for example, and a similar phenomenon has been suspected for the SARS coronavirus as well.
The results: In the most recent analysis out of MIT, which used data compiled by Johns Hopkins University, the researchers found that the maximum number of coronavirus transmissions has occurred in regions that had temperatures between 3 and 13 °C during the outbreak. In contrast, countries with mean temperatures above 18 °C have seen fewer than 5% of total cases. This pattern also shows up within the US, where southern states like Texas, Florida, and Arizona have seen a slower growth rate than northern states like Washington, New York, and Colorado. California, which spans north and south, has a growth rate that falls in between.
Other evidence: Two other preprint papers have drawn similar conclusions. The first, posted on Monday by two researchers from Spain and Finland, found that 95% of positive cases globally have thus far occurred at temperatures between -2 and 10 °C, which closely tracks with the MIT results, and in dry conditions. The second, posted earlier this month by a team led by researchers from Beihang University in China, also looked specifically at transmission rates across Chinese cities. It found that in the early days of the outbreak, before any government interventions, hot and humid cities saw a slower rate of spread than cold and dry ones.