Published 01 April 2020
Experts think that the transmission of coronavirus through food is unlikely, and currently, there is no evidence of the contagion spreading through contaminated food. So, why can't you get the disease from something you've eaten?
For evidence that food is an unlikely source or route of transmission of the virus, we can look to previous outbreaks of related coronaviruses, such as the (SARS-CoV) outbreak in 2003 and the Middle East respiratory syndrome coronavirus (MERS-CoV), which was first identified in 2012. Transmission through food consumption did not occur, and according to Marta Hugas the chief scientist of the European Food Safety Authority (EFSA) “At the moment, there is no evidence to suggest that coronavirus is any different in this respect.”
Scientists have identified several reasons that could make the transmission of the infectious agent through food less likely, even if the virus is present on the food or an infected person handles a food product.
First, unlike bacteria, viruses such as severe acute respiratory syndrome coronavirus 2 (the name given to the 2019 novel coronavirus) are not able to grow and multiply in food or water. Viruses are intracellular parasites, small packets of genetic material surrounded by a coat of proteins that only survive inside cells. They subvert the genetic machinery of their host cell to make lots of copies of themselves. Eventually, they burst through the cell wall, the microbiological equivalent of blowing up a building and then invade more cells.
As viruses require living cells to multiply, they are unable to grow in food and water. Therefore, the number of virus particles on or in food would be expected to decrease over time, not grow.
Second, the strict food hygiene rules that are already in place in the food industry, such as frequent handwashing and the careful cleaning of surfaces also reduces the likelihood of the transmission of coronavirus through food. Alcohols and surface-active agents, which are contained in soaps and detergents, are particularly good at dissolving the layer of fat (lipid layer) that surrounds the virus, which renders it inactive.
Scientists at France’s health and safety agency (ANSES) have suggested that in light of current scientific thinking, the only way the COVID-19 disease can be transmitted through food is if an infected person prepares or handles the food with dirty hands. However, the poor survivability of coronaviruses on surfaces means the risk is very low. In any case, the consensus scientific and medical opinion is that touching a surface with a virus on it, followed by touching one’s own face, is not the primary way the virus spreads.
Even if coronavirus particles were somehow to make its way into our food, the risk of infection would still be very low because of numerous obstacles in their path during cooking and eating. As with other members of the coronavirus family, this new virus does not like it hot and is sensitive to cooking temperatures. ANSES stated that “heat treatment at 63°C for four minutes (temperature used when preparing hot food in mass catering) can, therefore, reduce contamination of a food product by a factor of 1,000.”
Also, coronavirus is a respiratory infection that attaches to and reproduces inside tissue in the lungs. Food does not get inhaled into the respiratory tract, where the virus takes hold and so could end up in the stomach. Here, it wouldn’t last long because of a hostile environment of stomach acids, bile and proteolytic enzymes.
While the risk of catching coronavirus from food remains very low, good hygiene practices will further reduce risk.