A VIRUS which can pose a risk to people with health problems has been found in shellfish on sale in Glasgow supermarkets.

Traces of Hepatitis E were found in mussels stocked in four city supermarkets, which have not been identified.

It is the first time the virus has been found in commercially sold shellfish harvested from Scottish waters.

Hep E is generally a mild disease causing flu-like symptoms, jaundice, tiredness, fever, and vomiting.

However, it can be more serious for those with an weakened immune system due to underlying health conditions.

Transmission via a blood transfusion or transplant (from a donor with HEV) can also result in serious complications for patients.

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Researchers said "caution" should be taken by anyone at higher risk from the virus and called for further UK studies into foodborne transmission of the infection.

Experts from Glasgow Caledonian University (GCU) tested 310 shellfish samples and discovered traces of the virus in eight blue mussels and one oyster.

The retail outlets are not identified in the study but three out of the five retailers sold shellfish in which the virus was detected.

The shellfish tested in the study was bought from four supermarkets in the Glasgow area and a fishmonger on the east coast.

Figures show the number of laboratory-diagnosed cases of HEV in Scotland increased from 13 in 2011 to 206 in 2016.

Hepatitis E can also be risky for preganant women but that strain of the virus was not identified in tests. 

Professor Hugh Pennington, a leading Scottish bacteriologist, said: "Hep E is usually mild but can become chronic in the immuno-suppressed.

"The infection is common in British pigs and has been found in shellfish before, but not in the UK.

"Shellfish thrive on sewage which they filter and it is much commoner in tropical countries but can be killed by cooking. My advice is don't eat raw meats including shellfish."

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Professor Linda Scobie, principal investigator of the GCU study, said: “We don’t know at what point in the food processing chain this contamination occurred.

“There are significant gaps in our knowledge with HEV in the UK, we don’t know how much virus is required to cause infection, unlike the norovirus where you only need a few particles to cause acute illness.

"What we do know is more people are being diagnosed and if they have particular medical conditions then they are at risk of becoming very ill.”

A spokesman for Food Standards Scotland said: "The study is unable to say if infectious virus is present, and it’s not possible to determine if the results are a food safety risk."