Scientists from the University of Hong Kong have found at which temperatures the novel coronavirus remains most and least active. According to them, the virus remains highly stable for a long time at a temperature of about +4 degrees Celsius. In the absence of disinfection, its activity begins to decline only after 14 days.
COVID-19 is very sensitive to high temperatures: it dies within five minutes at +70 °C. At +56 ° C, the virus remains active for less than half an hour, at +37 degrees - for no more than two days, and at a temperature of 22 degrees - for about a week.
On the outer side of medical masks the virus lives for at least a week at room temperature and relative humidity of 65 percent. Coronavirus stays on paper for less than three hours, on wooden surfaces and fabrics - for not more than two days, on glass - for less than four days, on stainless steel and plastic - for no longer than a week.
It is worthy of note that reusable face masks made of fabric, which many people tend to use nowadays instead of disposable medical masks (or due to the shortage of them) can be used repeatedly only after meticulous disinfection. As with disposable medical masks, cloth masks need to be changed every two to three hours of constant use.
As medical specialists all over the world emphasize, such masks are intended primarily for sick individuals in the first place. They can be effective only in combination with other prophylactic measures (avoiding contact, frequent washing of hands, disinfection of items and surfaces, etc.). In addition, the mask should be worn by people who provide medical care for sick individuals.
Healthy people can wear the mask when visiting public places, using public transport, but the effectiveness of the mask in such situations has not been proven. Disposable medical masks made of non-woven material should not be reused or disinfected.
Specialists from the Massachusetts Institute of Technology (MIT) found that 90% of cases of COVID-19 infection occurred at temperatures ranging from 3 to 17°C and absolute humidity from 4 to 9 g/m³. If their assumption is correct, warm and humid weather in the coming months may improve the situation in many countries of the Northern Hemisphere, whereas the situation in the countries of the Southern Hemisphere may worsen. However, this does not mean that coronavirus will not spread in countries with warm and humid climate.
For example, in Thailand, where temperatures remain at about 30 degrees Centigrade all the year round, coronavirus remains active and tough measures to combat it. At the same time, the novel virus is now actively spreading in Syria and turkey, where temperatures already near +25C. Some specialists believe that climate shows no influence on the new coronavirus as it has spread on all continents, except Antarctica. This is just an observation as there is still no scientific base to explain the nature of the new coronavirus.