The emergence of SARS-CoV-2, the virus responsible for COVID-19, introduced widespread public concern regarding its stability and potential routes of transmission. Attention turned toward common household items, particularly food and food packaging, as possible sources of contamination. Understanding how this virus behaves outside of the human body, especially in common storage environments, is important for managing daily risks. This article examines the science behind the virus’s survival in cold temperatures and addresses the practical risk of infection from food products.
How Freezing Affects Virus Survival
Freezing does not destroy the SARS-CoV-2 virus; instead, low temperatures can preserve it for extended periods. Extreme cold stabilizes the virus’s outer structure, effectively putting it into a state of suspended animation rather than inactivating it. Studies using surrogate viruses similar to SARS-CoV-2 demonstrated that they could remain viable on various food surfaces for weeks.
Research involving surrogates on frozen meat products, including beef, chicken, pork, and salmon, showed that the viruses survived for up to 30 days when stored at freezer temperatures of -20°C (-4°F). This prolonged survival contrasts sharply with other methods of sanitation, such as heat, which quickly destroys the virus’s integrity. The primary function of freezing is to stop bacterial growth and preserve food quality, not to sanitize against viral contamination.
Assessing the Risk of Foodborne Transmission
The risk of contracting COVID-19 from touching food or food packaging is considered low by major public health organizations, including the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO). The virus is primarily a respiratory pathogen, spreading through person-to-person contact via respiratory droplets from talking, coughing, or sneezing. It is not considered a foodborne illness.
Although viral particles can theoretically be transferred to surfaces or packaging (fomites) and then to a person’s hands, this is not the main way the virus spreads. For an infection to occur, a sufficient quantity of viable virus must transfer from the surface to the hand, and then be transferred to the mouth, nose, or eyes. Furthermore, the acidic environment of the stomach is known to inactivate the virus, meaning ingestion of contaminated food is highly unlikely to cause illness. No cases of COVID-19 have been reliably linked to the consumption of food.
Essential Food Safety Practices
While the risk from food is minimal, standard food safety and hygiene practices remain the most effective steps to reduce general contamination risks. Hand washing is the single most effective barrier to prevent the transfer of germs. You should wash your hands with soap and water for at least 20 seconds before and after handling any food or food packaging.
It is important to clean and sanitize food preparation surfaces, such as countertops and cutting boards, with hot, soapy water after each use. Proper cooking temperatures also serve as a safeguard, as heat easily inactivates the virus. Ensuring that meat, poultry, and eggs are cooked to their recommended internal temperatures will destroy any potential viral contamination. Avoid washing raw meat or poultry, as this action can inadvertently spread surface bacteria or viruses to other surfaces in the kitchen.