Sunlight and high temperatures help stop the spread of coronavirus on hard surfaces, according to preliminary results of a study for the US Government.
Sunlight and high temperatures help stop the spread of coronavirus on hard surfaces, according to preliminary results of a study for the US Government.
Sunlight and high temperatures help stop the spread of coronavirus on hard surfaces, according to preliminary results of a study for the US Government.
Covid-19 also struggles to survive on surfaces in high humidity, the results suggest, adding to hope that a summer heatwave could help ease the health crisis.
A briefing by scientists working on behalf of the Department of Homeland Security at the White House reportedly found the risk of "transmission from surfaces outdoors is lower during daylight".
"Sunlight destroys the virus quickly," reads the document, initially leaked to the Yahoo News website.
The results cautioned, however, that enclosed areas with low humidity, such as airplane cabins, "may require additional care to minimise risk of transmission."
The DHS declined to answer questions about the findings, which are yet to be published, but scientists in charge of a similar study in London told The Telegraph the results were no surprise.
The Telegraph disclosed last month how researchers at the UCL Institute of Health Informatic found infections from three common coronaviruses followed a seasonal pattern in England, with large numbers occurring during winter, and roughly at the same time as influenza.
Cases peaked in February, but only small amounts of the virus were transmitted in the summer months, with infections dropping rapidly from May and not ramping up again until the end of the year.
"Our findings support the idea that in the UK we could see continued but lower levels of coronavirus transmission in the summer, but this may reverse in the winter if there is still a large susceptible population at that point," Dr Rob Aldridge, of UCL, said.
"However, given this is a novel virus, we don't know if this seasonal pattern will hold over the summer due to high levels of susceptibility in the population. For this reason, it is crucial that we all act now to follow current health advice. Washing your hands and staying at home means you not only reduce your risk of getting COVID-19, but you are also protecting others by greatly reducing the chances of the virus spreading further in the community."
The findings are in line with previous research in other countries showing that coronaviruses are seasonal in winter in temperate climates, with greater variation in tropical regions.
A separate review from Yale University also found that the cold, dry air of winter helps coronavirus to spread among people. But as humidity increases during spring and summer, the risk of transmission of the virus through airborne particles decreases both outside and indoors in places such as offices.
