Virus lives for three weeks on frozen food

COVID-19 can survive on frozen meat and fish for up to three weeks, a study has found, as scientists warn that contaminated food may cause outbreaks.

Individual pieces of salmon, chicken and pork from supermarkets in Singapore were sliced into cubes then a sample of the virus was added to them.

The meat and fish were stored in conditions that simulate those used to transport food between countries, which is 4C (standard refrigeration temperature) and minus 20C (standard freezing temperature). Scientists found that infectious Covid-19 was still present on the samples after 21 days.

They are now warning that this may explain outbreaks in countries that have not had any cases for long periods – and could lead to future spikes.

The study states: “An explanation is required for the re-emergence of outbreaks in regions with apparent local eradication. Importation of contaminated food and packaging is a feasible source for such outbreaks.

“While it can be confidently argued that transmission via contaminated food is not a major infection route, [it] is an important hypothesis. An infected food handler has the potential to become an index case of a new outbreak.”

Prof James Wood, head of the veterinary medicine department at the University of Cambridge, told The Sunday Telegraph: “The authors discuss, very sensibly, how it is important that factory workers must be incentivised not to go to work when symptomatic or in contact with Covid-19 cases.”

The study, which is yet to be peer reviewed, was published on the bioRxiv website.