Study finds that SARS-CoV-2 can last for more than a month on frozen berries

At the start of the COVID-19 pandemic, concerns were rife as researchers around the world scrambled to learn more about the ways the virus was transmitted.

One concern was the possibility of the virus being transmitted through food. While the US Centers for Disease Control and Prevention has since reported that there is no evidence to support food-related transmission of SARS-CoV-2, concern about the persistence of the virus on food prompted a study recently published in the Journal of Food Microbiology. University of Georgia food scientists began the study in 2021 to create a preventative method for measuring virus on foods and determining whether the virus could persist in fresh or frozen berries.

The event was led by Malak Al-Saili, researcher at UGA study To address concerns about food transmission of SARS-CoV-2, which persists despite reports from the Centers for Disease Control and Prevention that there is no evidence to support food-related transmission of the virus.

Malak Al-Aseeli, associate professor at the Center for Food Safety in the College of Agricultural and Environmental Sciences, said the research team chose to study berries because they are known as “universal compounds” for transmitting other foodborne viruses, such as norovirus.

“The takeaway is that if people are concerned about the virus, washing fruits or vegetables can remove 90% of the virus,” Al-Osaili said. “One concern was that the virus was found to be stable on frozen berries and so could be shipped from one country to another.”

According to the study results, SARS-CoV-2 that was experimentally introduced to berries remained infectious on frozen berries for at least one month, while cooling at 39°F showed a 90% reduction in SARS-CoV-2 infection over three days. The results of the study showed that washing berries with water before freezing reduced SARS-CoV-2 infection by 90%, confirming the importance of food safety measures in preventing initial contamination.


According to a UGA Center for Food Safety study, SARS-CoV-2 that was experimentally introduced to berries remained infectious on frozen berries for at least a month. Refrigerating berries at 39 degrees Fahrenheit showed a 90% reduction in SARS-CoV-2 infection over three days, as did washing the berries before freezing.

Al-Osaili said: “We still believe that the respiratory pathway is a much more important means of transmission, but this is something to consider, and measures should be taken to eliminate this possibility.”

Commercially prepared frozen berries may be a concern because they are not cooked before consumption.

“This is important when food is being served to populations that are already at risk, such as the elderly, the immunocompromised, individuals in hospitals, and people with underlying medical conditions,” Al-Sili said.

She added that for individuals who buy fresh fruit, proper washing before eating, refrigeration or freezing can significantly reduce risk.

“This is not something to worry about with fresh berries. You can just wash them and eat them or store them in your refrigerator. Only frozen fruit would be a concern if there was virus contamination.” Also, this is something the food industry should consider from a perspective. Biosecurity or food defense. If companies follow food sanitation and hygiene protocols and remove sick workers from the production line, the risks will be greatly reduced.”

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