When the COVID-19 pandemic began, not much was known about SARS-CoV-2 (the coronavirus) and its survival in food, various materials and surfaces. Since then, several food safety agencies have assessed the risk of acquiring the virus in contaminated food or food packaging. The consensus is that there is currently no evidence that it is a risk to food security.
The main route of infection is from person to person, through contact with each other, respiratory droplets and aerosols from coughing, sneezing and speech. Therefore, it is not considered a foodborne virus.
We searched the scientific literature to see what it said about food safety and SARS-CoV-2. This includes the survival of the virus, how it is transmitted and how it can be inactivated in food and surfaces.
Overall, the evidence suggests that the virus is not a food safety risk. But it caused 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 found viral genetic material in anal swabs and blood drawn from patients. This was an important point because one of the symptoms of COVID-19 is diarrhea. However, there are no reports to date showing the fecal-oral transmission of the virus.
In addition, several studies have concluded that diarrhea in patients with COVID-19 is not likely to occur due to eating contaminated food. Instead, it comes from the virus pathway, from the respiratory system to the digestive tract.
Where the coronavirus survives
Viruses tend to survive well in low temperatures. Freezing can actually preserve them. Therefore, SARS-CoV-2 is likely to survive freezing food. But several studies have indicated that this virus and others like it are inactivated by cooking food at frequently used temperatures.
The coronavirus appears to be stable at different pH values (3–10) at room temperature. More alkaline and more acidic conditions beyond this range appear to inactivate the virus. This means that it is unlikely to survive the acidic environment of the stomach.
It is also likely that the virus in the food is in low concentrations. It is important to note that the coronavirus, like other viruses, cannot multiply outside its hosts. Therefore, it cannot multiply in food.
It is well established that viruses that cause respiratory infections can be transmitted by indirect contact through the environment. This happens when a person touches contaminated surfaces and then touches his mouth, nose or eyes, without first washing his hands.
Several experimental studies on coronavirus survival on different types of surfaces under different conditions have been carried out. The virus was found to survive on different surfaces for different periods of time, depending on environmental conditions and the initial viral load.
However, one must be aware that survival may be different from these studies, in a more realistic scenario, outside the laboratory. The United States Centers for Disease Control and Prevention and other similar agencies and organizations do not consider contaminated surfaces to be the primary route of transmission of SARS-CoV-2.
The current consensus is therefore that SARS-CoV-2 is not transmitted by food and is highly unlikely to be transmitted by food packaging, but it can spread by touching contaminated surfaces and then touching your mouth, nose or eyes. Therefore, it is very important to properly clean and disinfect food contact surfaces and, especially, high contact surfaces and utensils in a food environment.
Disinfection and prevention
SARS-CoV-2 belongs to the family of enveloped virus coronaviruses, which makes them susceptible to detergents and a variety of other microbicides, even more than fungi, vegetative bacteria and yeasts.
Studies have shown that the fat layer surrounding the virus is broken, leading to virus inactivation when using 0.1% sodium hypochlorite (diluted household bleach), 0.5% hydrogen peroxide and 62% -71% ethanol. All of these solutions significantly reduce SARS-CoV-2 on surfaces after one minute of exposure.
Several agencies have published a list of disinfectants approved for use against SARS-CoV-2 in industrial environments, including the United States Environmental Protection Agency, Health Canada and the European Union.
In conclusion, the biggest risk related to COVID-19 continues to be person-to-person transmission and aerosol transfer in the food environment, including manufacturing, retail and food services. In fact, there have been several outbreaks of COVID-19 from person to person among farm workers and in food processing establishments.
Dusan Petkovic / shutterstock
That is why it is important to adhere to the appropriate hygiene measures, using appropriate personal protective equipment (such as masks) and practicing proper hand hygiene and physical distance. Food companies – like any other – need to ensure that their employees are attentive to the use of masks, hand washing, maintaining physical distance and regularly cleaning and disinfecting surfaces and high-contact utensils.
In summary, the discovery of SARS-CoV-2 in foods or food packaging may raise concerns about food safety, but does not indicate a public health risk. Therefore, it should not be a basis for restricting the food trade or initiating a food recall. Thinking about the food supply chain in a connected way – integrating health, food security and sustainability – will be an important part of controlling any future pandemics.