Previous studies were based on PCR test to detect virus RNA and did not try to cultivate a living pathogen, said researchers in London, writes liga.net.
Scientists have not been able to find capable of infection of the coronavirus SARS-CoV-2 on contaminated surfaces, and to study took swabs from hospitals at the peak of the epidemic. Preprint report of the group of authors from Imperial College London published on the server medRxiv.
Note: the article has the status of a Preprint. This means that the results of the report, until confirmed by independent expert assessment as is common in science, so they should not be used for clinical practice. During a pandemic there is a lot of research – expert panels do not have time to treat them promptly.
Samples were collected from 2 to 20 April using a cotton swab on an area of 25 cm2 in the offices of a group of hospitals in North-West London. While all hospitals have been fully occupied with patients with COVID-19. The virus tried to cultivate in Vero E6 cells (kidney African green monkey) and Caco2 (colon cancer person).
Summary: the viral genome was found in 114 out of 218 (52.3 percent) of surface and 14 of 31 (38.7 per cent) of air samples, however, the virus are unable to cultivate. In addition, detected on surfaces in the hospital levels virus RNA was below the minimum that can be cultivated in two hours after the Deposit of the pathogen.
The authors added: viral RNA could be on the surface to collect samples for more than two hours: “We are unable to find out, our inability to cultivate the virus due to the low level of RNA or the amount of time since the deposition of the pathogen on surface, or both reasons.”
Previously there have been numerous studies that showed that SARS-CoV-2 supposedly can “survive” on dry surfaces and in aerosols from several days to weeks, especially on smooth surfaces. But still the understanding of the role of contamination of the surface and air in the transmission of SARS-CoV-2 is limited, the scientists write.
The centers for control and prevention of diseases of the U.S. write: “the Transfer of a new coronavirus to people with surfaces infected with the virus have not been documented; it occurs more often using microdroplets from an infected than through objects and surfaces”, but at the same time encourage all to disinfect.