COVID-19: Warmer temperature had little effect on infection spread, claims study

Transmission of coronavirus varies seasonally, but warmer temperatures are not enough to prevent the spread, new research conducted by Imperial College London revealed. The study showed that temperature and population density were the most important factors in determining the rate of virus spread, but only in the absence of mobility restrictions like lockdown and border restrictions. According to researchers, policy interventions played many significant roles than environmental factors when it came to curbing coronavirus contagion.

'Government mustn't drop policies' 

The study, which is the first to incorporate environmental data into the epidemiological model, was published in the Proceedings of the National Academy of Sciences on June 10. In the aftermath of the publication, lead author Dr Tom Smith said that the study depicts that temperature changes have a much smaller effect on transmission than policy interventions, “so while people remain unvaccinated, governments mustn’t drop policies like lockdowns and social distancing just because a seasonal change means the weather is warming up”. However, he said that lower temperature in the winters and autumn may lead to a speedy transmission of the virus in the absence of administrative policies.

The study had several drawbacks, as per the researchers. Firstly, it had been difficult to quantify the effects of environmental factors including temperature, humidity, and UV radiation (sunshine) on SARS-CoV-2 transmission. Secondly, differences in case counting and policy intervention in different countries also makes it difficult to compare environmental factors on a global scale. The COVID 19 pandemic which originated in December 2019 continues to wreak havoc across the world and has infected over 175,216,260 people across the world.

“While temperature and population density do influence SARS-CoV-2 transmission, our findings re-confirm that the most important drivers are public policy and individual behaviour. For example, during lockdowns, there was no meaningful signature of temperature influencing transmission," said Lead researcher Dr Will Pearse.

This comes as the United Nations warned that coronavirus may develop into a seasonal disease and said that there should be no relaxation in precautionary measures on the basis of meteorological factors. In the World Meteorological Organization Task Team first report, the experts have tried to find about meteorological and air quality influence on the spread of coronavirus. The report also said that there is some preliminary evidence that "poor air quality increases COVID-19 mortality rates" but not that pollution directly impacts the airborne transmission of SARS-CoV-2. 

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