Prime Minister Tony Abbott has assured Australians that all berry products involved in a Hepatitis A outbreak are being screened.

But it’s unclear who, if anyone, is carrying out the screening.

Mr Abbott told reporters on Thursday 100 per cent of “these sorts of imports” are now screened, despite not yet being classified as high risk by the food standards regulatory body FSANZ.

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“We have moved to 100 per cent screening of these sorts of imports until this matter is resolved in a way which is very protective of the health of the Australian public,” Mr Abbott said.

Mr Abbott is vague about who, if anyone, is carrying out screening.
 Photo: AAP

The Prime Minister’s office later clarified Mr Abbott was referring to the Patties Food products that were involved in the outbreak.

However a spokesman couldn’t confirm who was doing the testing.

The Department of Agriculture wouldn’t confirm any changes in screening but a spokesman said that parent company Patties Foods was voluntarily holding all products involved.

The frozen berries at the centre of the outbreak, branded in Australia as Nanna’s and Creative Gourmet, have been recalled and taken off shelves.

Frozen berries are classified low risk, and require only five per cent screening, but the department has requested a review of that status.

High risk imported foods must be 100 per cent screened.

Comment has been sought from Patties Foods.

Berry-linked hepatitis A spreads

A person has contracted Hepatitis A from frozen berries in WA. Photo: Shutterstock

There are now 22 South Australian schools and children’s centres, which include childcare centres, on alert for possible cases of hepatitis A over the consumption of frozen berries.

By Thursday morning, 13 people had been diagnosed with Hepatitis A in Queensland, NSW, Victoria and Western Australia.

That number could rise over the coming weeks, with the Department of Health saying one in 100 people who ate the berries could be infected.

Meanwhile, Victoria’s Ballarat High School year seven students have been informed they ate Hepatitis A linked berries after making smoothies during a cooking class.

On Wednesday it was confirmed a spate of hepatitis A cases understood to be caused by contaminated frozen berries, had spread to Western Australia.

The WA case is believed to be the first detection of hepatitis A allegedly caused by the Nanna’s brand of frozen berries, a Department of Health spokesman said.