According to a team of Chinese researchers, the international business of salmon, a common name for several species of ray-finned fish, may have caused the pandemic as the coronavirus can survive for over a week on the scales of chilled fresh salmon, according to a report in South China Morning Post .
The researchers said the virus could remain infectious for eight days when the fish was stored at a temperature of 4 degrees celsius.
Researchers also said that Sars-CoV-2 remained infectious on the salmon for two days at 25 degrees, which they called “regular room temperature”.
However, the salmon is usually kept at 4 degrees in markets and during export-import. This tends to increase the lifespan of the virus by six days.
Dai Manman, lead researcher of the study, said in a non-peer-reviewed paper published in biorxiv.org: “Under such condition, (coronavirus) contaminated fish from one country can be easily transported to another country within one week, thus serving as one of the sources for international transmission.”
“This calls for strict inspection or detection of (the coronavirus) as a critical new protocol in fish importation and exportation before allowing sales,” he added.
According to the researchers, the insurgence and resurgence of the virus in China were also associated with wet markets that sold seafood.
Earlier in June, China had suspended the import and export of salmon in order to contain the spread of the virus.
Dai further added: “The cases in Wuhan and Beijing created concerns that fish or meat-attached SARS-CoV-2 could be a potential source of Covid-19 transmission.”
Another study reported by the Telegraph UK in August indicated that Covid-19 infected frozen food can cause outbreaks as the virus doesn’t get killed in freezing temperatures.