On April 27, a study published in the journal Nature proved that the new coronavirus (sars-cov-2) RNA could be detected in the air.
The corresponding author of the study is Lan Ke, director of the State Key Laboratory of Virology, Wuhan University and professor of the school of life sciences.
According to reports, the environmental monitoring of two hospitals and some public areas in Wuhan revealed that there are hot spots of air borne virus RNA, but whether sars-cov-2 RNA has the potential of infection has not been evaluated. Although the sample size is small (31 sites, less than 40 samples), this finding confirms the previous view that careful hygiene, good ventilation and avoidance of aggregation can reduce the risk of exposure to airborne viruses.
The reported transmission patterns of sars-cov-2 include: close contact with infected persons; contact with contaminated surfaces; inhalation of droplets released from respiratory system of infected persons. It is unclear whether sars-cov-2 is likely to spread further through the air.
In novel coronavirus pneumonia hospital, from February 2020 to March, the two sets of aerosol capture devices were set up inside and around the two new crown pneumonia treatment hospitals. One was the third class hospital for critically ill patients, the other was the shelter hospital for the patients with mild diseases. In the ventilated area, the concentration of virus RNA in air is very low, which is attributed to the high efficiency of effective isolation and air exchange; the toilet used by patients is not ventilated, and the concentration of virus RNA is high. The authors found that the virus RNA concentration was particularly high in the place where the medical staff removed the protective device, which means that after the protective device was removed, the aerosol containing the virus could be suspended in the air again. However, after increasing the intensity and frequency of cleaning and disinfection, no evidence of air borne sars-cov-2 RNA was found in the medical staff area.
In public areas outside hospitals, such as residential buildings and supermarkets, the concentration of sars-cov-2 RNA is generally low. However, the concentration of sars-cov-2 RNA was still high in two places with large-scale population, including the outdoor open space near one of the above-mentioned hospitals. The authors suggest that individuals infected with sars-cov-2 in these crowded areas may contribute to the generation of viral aerosols.
The study did not investigate whether sars-cov-2 RNA might be infectious, and hospital access was limited during the peak period of the epidemic, limiting the number of samples available. Nevertheless, this study supports the practice of reducing the risk of infection by thoroughly eliminating potential hot spots of viral aerosols, keeping hospitals well ventilated and avoiding aggregation.