tic consumers ( Fig. 2 a). In 2019 and 2020, China's imports of foreign foods reached 90.8 and 107.7 billion in U.S. dollars, respectively ( CFSN, 2021 ). The number of countries and regions exporting foods to China also increased from 108 to 170 between 1997 and 2017 ( iResearch, 2019 ). Based on a survey of domestic consumers ( n = 1000) in China in April 2019, 21.7 % of survey respondents indicated that >20 % of their food varieties were imported ( Fig. 2 b). Fig. 2. Open in a new tab (a) China's growing demand for imported foods from 2009 to 2019, in billions of U.S. dollars, based on statistics by the General Administration of Customs of the People's Republic of China ( iResearch, 2019 ). (b) Percentages of imported foods in total food consumption, from a survey of domestic consumers ( n = 1000) in China by iResearch/iClick in April 2019 ( iResearch, 2019 ). Most fresh foods rely on refrigerated facilities, or cold chains, for storage and long-range transport, which involve a long and complex process to maintain a confined, low-temperature environment with workers and facilities potentially contacting food items along the process. Meanwhile, foods transported via the cold chain also provide ideal carriers for coronaviruses, including SARS-CoV-2 and its variants ( Han et al., 2021 ). After the initial harvesting and processing, the constant low-temperature conditions maintained throughout the storage, transport, and retailing of fresh foods are highly amenable to the survival of SARS-CoV-2. It is known that some coronaviruses, such as the SARS-CoV-1 which shares 79.6 % of its genome sequences with the novel coronavirus (SARS-CoV-2), are extremely persistent under freezing conditions (up to two years at −20 °C), compared with their survival under normal temperatures ( WHO, 2020c ). Other coronaviruses, such as the middle east respiratory syndrome coronavirus (MERS), the bovine coronavirus strain (BCoV-88), and the human coronavirus 229E (HCoV-229E), also show 1 The authors contributed equally. 10 4 2023 5 1 2023 868 425380 161388 161388 12 8 2022 16 12 2022 1 1 2023 05 01 2023 05 01 2023 15 09 2024 © 2023 Published by Elsevier B.V. 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Since the broke out of the novel coronavirus disease at the end of 2019, nearly 650 million people have been infected around the globe, and >6.6 million have died from this disease. With increasing reports from China showing that the cold chain might spread the coronavirus disease, questions and concerns have been raised recently, and a series of control measures were implemented in China to mitigate the risks of virus transmission via imported cold-chain foods. Apart from those efforts, however, public health authorities around the world have generally taken a laxed approach. On August 13, 2020, speaking during a press briefing in Geneva, Dr. Travel restrictions, lockdowns, and community-wide testing were implemented in places with active spread of the novel coronavirus. Those early interventions quickly brought its domestic infections under control. The daily new cases of COVID-19 infections eased to low levels since late March 2020, with local eradication reported in most parts of the country. Fig. 1 shows the number of confirmed cases and the evolving daily infections in mainland China between April 2020 and December 2021. Yet, the country was still prone to re-emergent outbreaks potentially caused by infected travelers or contaminated foreign goods arriving in the country. After the initial harvesting and processing, the constant low-temperature conditions maintained throughout the storage, transport, and retailing of fresh foods are highly amenable to the survival of SARS-CoV-2. It is known that some coronaviruses, such as the SARS-CoV-1 which shares 79.6 % of its genome sequences with the novel coronavirus (SARS-CoV-2), are extremely persistent under freezing conditions (up to two years at −20 °C), compared with their survival under normal temperatures ( WHO, 2020c ). A simulated experiment conducted at the Xinfadi Market, i.e., the epicenter of the re-emergent outbreak in Beijing in June 2020, showed that even a mildly contaminated product could lead to massive spreading ( Li et al., 2021 ). Researchers used fluorescent microspheres as surrogates for the novel coronavirus to simulate the virus spreading. Their results showed that even products contaminated by a small amount of the surrogates could spread widely Specifically, authorities have mandated the requirements on the product sampling and nucleic acid testing on imported cold-chain foods before they enter centralized storage facilities ( JPCMSC, 2020b ; BDCP, 2020 ; NHC, 2020b ). After being sampled and tested for the novel coronavirus during customs inspections, the surfaces of those goods must be disinfected before contacting with domestic workers. While it is the COVID-19 pandemic that brought this issue to the public's attention, it is worth noting that other human pathogens, including but not limited to those in the coronavirus family, may also transmit to humans via those goods and facilities. The human influenza viruses, for instance, could remain contagious for 30–160 days at 4 °C ( Poulson et al., 2016 ).