According to the research findings published by Dale Fisher of the Division of Infectious Diseases at the National University Hospital of Singapore, entitled Seeding of outbreaks of COVID-19 by contaminated fresh and frozen food, it was demonstrated that SARS-CoV-2 can survive at temperatures relevant to international food trade transport and storage conditions. After 21 days at 4°C (refrigerated standard) and -20°C (frozen standard), there was no decrease in the infectivity of SARS-CoV-2 added to chicken, salmon, and pork. The cold environment created by the cold chain provides a good space for the virus to survive. Once COVID-19 is shown to be transmitted through virus-contaminated surfaces, it will represent a new public health challenge for countries and regions where the pandemic has been contained.
Cold chain products will be contaminated by COVID-19, and the viral load is relatively high. Secondly, the surface of cold chain products will be polluted by COVID-19, and it can still be spread to special employees through contact after shipping. Third, COVID-19 contaminated products may become a hidden route of transmission in COVID-19. After being stored in cold storage for months or even years, the virus may still infect relevant workers, which leads to the secret transmission in "relatively old" COVID-19.
In the face of repeated COVID-19 epidemics in various countries, should countries further strengthen their epidemic prevention measures? First, strengthen COVID-19 monitoring for cold chain workers around the world to prevent products from being contaminated by viruses. It is suggested that industry employees who are often in close contact with cold chain products with high COVID-19 pollution at work, such as those engaged in handling, processing and selling of cold chain products, should enhance their awareness of protection, do a good job of daily protection, avoid direct skin contact with potentially contaminated cold chain products, do not take off their possibly contaminated overalls after contacting cold chain products, and do not touch their nose, mouth and eyes before hand washing and disinfection. After work is completed, they should immediately wash their hands and disinfect them regularly, so as to find infected people as soon as possible. Second, monitor the virus RNA of imported cold chain products. Thirdly, employees in the industry who are often in close contact with cold chain products with high possibility of COVID-19 virus pollution, such as those engaged in handling, processing and sales of cold chain products, will be included in the high priority group in COVID-19 vaccine plan.
