When the COVID-19 pandemic started, not much was known about SARS-CoV-2 (the coronavirus) and its survival in food, on different materials and on surfaces. Since then, several food safety agencies have assessed the risk of possible contamination with the virus from contaminated food or food packaging. The consensus is that there is currently no evidence that it is a food safety risk.
The main route of infection is from person to person through contact with each other, breathing drops and aerosols through coughing, sneezing and talking. Hence, it is not considered a foodborne virus.
We have examined the scientific literature to see what it says about food safety and SARS-CoV-2. This included the survival of the virus, how it is transmitted, and how it can be inactivated in food and on surfaces.
Overall, the evidence suggests the virus does not pose a food safety risk. But it has created disruptions in the global food supply chain.
A research question was whether the virus is transmitted via the fecal-oral route. The question arose because a study had found viral genetic material in anal swabs and blood from patients. This was an important point because one of the symptoms of COVID-19 is diarrhea. However, there have been no reports of fecal-oral transmission of the virus to date.
In addition, several studies have concluded that diarrhea in COVID-19 patients is unlikely to occur from ingestion of contaminated food. Rather, it is from the path of the virus, from the respiratory system to the digestive tract.
Where the coronavirus survives
Viruses tend to survive well in low temperatures. Freezing can even preserve them. Thus, it is likely that SARS-CoV-2 would survive food freezing. But several studies have shown that this virus and similar viruses are inactivated by cooking food at commonly used temperatures.
The coronavirus appears to be stable at various pH values (3-10) at room temperature. More basic and more acidic conditions outside this range seem to inactivate the virus. This means it is unlikely to survive the acidic environment of the stomach.
It is also likely that the virus is present in low concentrations in food. Importantly, like other viruses, the coronavirus cannot multiply outside of their hosts. Therefore, it cannot multiply in food.
It is well known that viruses that cause respiratory infections can be transmitted through indirect contact through the environment. This happens when a person touches contaminated surfaces and then touches their mouth, nose, or eyes, without washing their hands first.
Several experimental studies have been done on the survival of the coronavirus on different types of surfaces under different conditions. The virus was found to survive on different surfaces for different periods of time, depending on the environmental conditions and the initial viral load.
Nevertheless, one should be aware that survival may be different from these studies, in a more realistic setting, outside of the laboratory. The U.S. Centers for Disease Control and Prevention and other similar agencies and organizations do not consider contaminated surfaces to be a major route of transmission of SARS-CoV-2.
The current consensus, therefore, is that SARS-CoV-2 is not and most likely not transmitted by food packaging material, but it can be spread by touching contaminated surfaces and then touching your mouth, nose or eyes. It is therefore very important to properly clean and disinfect surfaces that come into contact with food, and especially surfaces and utensils that touch a lot in a food environment.
Disinfection and prevention
SARS-CoV-2 belongs to the coronavirus family of enveloped viruses, making them more susceptible to detergents and a variety of other microbicides, even more so than fungi, vegetative bacteria and yeasts.
Studies have shown that the fat layer around the virus is disrupted leading to inactivation of the virus when using 0.1% sodium hypochlorite (diluted household bleach), 0.5% hydrogen peroxide and 62% -71% ethanol. These solutions all significantly reduce SARS-CoV-2 on surfaces after one minute of exposure.
Several agencies have published a list of approved disinfectants for use against SARS-CoV-2 in industrial settings, namely the United States Environmental Protection Agency, Health Canada and the European Union.
In conclusion, the greatest risk related to COVID-19 remains person to person transmission and aerosol transmission in the food environment, including manufacturing, retail and food service. In fact, there have been several person-to-person COVID-19 outbreaks among agricultural workers and in food processing plants.
Dusan Petkovic / shutterstock
It is therefore important to take proper hygiene measures by wearing appropriate personal protective equipment (such as masks) and by maintaining good hand hygiene and physical distance. Food companies – like everyone else – must ensure that their employees are vigilant about wearing masks, washing hands, keeping a physical distance and regularly cleaning and disinfecting touch-sensitive surfaces and utensils.
In summary, the discovery of SARS-CoV-2 on food or food packaging may raise concerns about food safety, but it does not indicate a risk to public health. Therefore, it should not be a basis for restricting trade in food or initiating a food recall. Thinking in a connected way about the food supply chain – integrating health, food security and sustainability – will be an important part of managing potential future pandemics.