SARS-CoV-2 have an aversion to hot-humid weather?
A recent study shows that nine out of ten infections with the new Coronavirus SARS-CoV-2 occur in regions where the average daily temperatures of between three degrees Celsius and 17 degrees Celsius were. In addition, the absolute humidity was in the regions four to nine grams per cubic meter. The American research team predicts that the summer can be used to subdue the pandemic.
Researchers from the Massachusetts Institute of Technology examined the scheme of the spread of the new Coronavirus SARS-CoV-2 and found that the Virus spread particularly strongly in countries with similar weather conditions were conditions like in China at the time of the outbreak were prevalent. In China, the middle countries with warmer and humid climates like Singapore, Malaysia, Thailand and other Southeast Asian countries, are recorded at rates markedly lower growth. The results were recently published in the journal “Social Science Research Network”.
Similar Weather Conditions
The research team found that the disease numbers have risen most in the countries in which similar weather conditions as in the heavily affected Region of Hubei in China. We want to see the study team suggests that in Italy, Iran and South Korea at the time of the rapid spread of similar weather conditions in Wuhan and other Chinese cities, where the Coronavirus was spreading heavily.
SARS-CoV-2 seems to avoid warm regions
The Virus seems to prefer a daily average temperature between 3°C and 10°C with a humidity of 4 to 9 g/m3. This Hypothesis is also supported by the fact that the Virus spread in the warmer regions, such as Thailand, which are located in direct proximity to China, is less strong. In addition, the researchers showed that there are within the United States, a conspicuous North-South gradient in the spread. In the cooler countries of the North more and more diseases are discovered than in the warmer States of the South. Even within California, the number of cases in the North was twice as high as in the South.
There are, however, two States that do not fit into this picture. For this purpose, the state of Oregon, the recorded despite the relatively northerly position of the non-diseases, and the state of Louisiana, have been reported in which despite the southern location, a relatively large number of disease counts.
SARS-CoV-2 seems to prefer dry air
In addition, the Team research leader Qasim Bukhari stated that up to 11. March 2020, 90 percent of all infections in places occurred, in which the absolute humidity is between 4 and 9 g/m3. In any case, a high humidity for the spread of respiratory diseases is a hindrance.
Similar observations from China
Similar observations are also described Chinese researchers from Tsinghua University. They reported that in 100 Chinese cities, the Rate of new infections has declined, as the temperature and humidity rise.
The Chinese researchers calculated that decreases by increasing temperature and humidity, the so-called basic reproduction number. This number indicates how many people one sick Person will infect. This value is 1, the Sick infects another Person. To stop an epidemic, you would have to decrease this value below 1. The Robert Koch Institute estimates the basic reproduction number of Covid-19 2.4 to 3.3. The Chinese research team calculated that for each degree Celsius of temperature, the basic reproduction number increase 0,0383 drops. In addition, the number declining further 0,0224 per 1 percent increase in relative humidity.
The actual influence will show up soon
Whether the two research teams is right, it will show in the coming months. The researchers emphasize, however, that the results suggest that SARS can’t spread CoV-2 in warm areas. The calculations are based on the currently available data and there is many unknown factors. Many virologists such as, for example, Christian Drosten also emphasize that a rise in temperature could be conducive to curb – this alone, but most likely will not be enough to stop the epidemic. (vb)
Also read: COVID-19-diseases: the Rate in the last week in Germany fell.