A new study published in the journal Applied and Environmental Microbiology has found that SARS-CoV-2 surrogate viruses can survive on meat products in the refrigerator or the freezer for up to a month. These findings highlight the need for rigorous and sustained food sanitation and hygiene during the processes of harvesting, transporting, processing, and distributing these foods.
The experiments were conducted using chicken, pork, beef, and salmon that were exposed to surrogate viruses with spikes similar to those of SARS-CoV-2 – one RNA virus with a lipid envelope (Phi 6), and two animal coronaviruses (the murine hepatitis virus and the transmissible gastroenteritis virus). The meat products were then stored at both refrigeration (4oC) and freezer temperatures (-20oC). This investigation was sparked by the fact that certain Covid-19 outbreaks in Southeast Asia seemed to occur without prior community transmission, suggesting that packaged meat products produced in areas with high coronavirus community transmission could have been the source of the outbreaks.
The analysis revealed that these viral surrogates could survive for extended periods of time at high concentrations at both refrigerated and frozen temperatures. “The ability of SARS-CoV-2 viral surrogates like Phi 6 and animal coronaviruses to survive for varying extents on some meat and fish products when stored refrigerated or frozen is a significant and concerning finding,” wrote the study authors.
“Continued efforts are needed to prevent contamination of foods and food processing surfaces, worker hands, and food processing utensils such as knives, and there is a need to better address the lack of or inadequate disinfection of these foods prior to meat packaging.”
A limitation of the study is that researchers used surrogate coronaviruses instead of SARS-CoV-2 itself. Although these viruses have been found in previous studies to be reliable models for the survival of SARS coronaviruses under different environmental conditions, the differences in virus survival among the surrogates that were observed during the study suggest that one indicator virus may not always be predictive of the behavior of SARS-CoV-2.
“Further studies of this type that included SARS-CoV-2 are needed, especially studies that better characterize and quantify the effects of physical, chemical, and biological factors, including temperature, water activity, relative humidity, pH, surface electrical potential, hydrophobicity, chemical activities such as enzymes and surfactants, and microbiological activities such as from other microbes on and in foods,” said the study authors.
“As reports continue to emerge about the potential spread of SARS-CoV-2 through contaminated food products and the continued emergence of variants of concern, a greater understanding of the survival of these viruses at low temperatures on meat and fish products as well as other foods is needed and should be encouraged.”
By Andrei Ionescu, Earth.com Staff Writer