Hepatitis A infections continue to rise as three cases confirmed in Queensland

• Frozen berries evidence crucial for compensation claims

UPDATE Monday 10.30pm: Recall extended to 1kg bags Nanna's Raspberries with 'best before' dates up to and including BBD 15/09/2016. Source: NSW Food Authority

Health experts expect the number of Australians to contract Hepatitis A from frozen berries to increase after three new infections emerged in Queensland.

Eight people have now contracted the virus after eating frozen mixed berries, including three diagnosed in Victoria, two in NSW, and the three Queensland cases reported on Monday.

A ninth person, also from Queensland, has tested positive to the virus but the state's health department says it's unclear if they consumed the suspect berries.

Patties Foods is conducting a nationwide recall of Nanna's Frozen Mixed Berries 1kg packs and Patties' 300g and 500g packs of Creative Gourmet Mixed Berries, as a precautionary measure.

Senior director of Queensland Health's communicable diseases unit, Dr Sonya Bennett says it's inevitable more cases will emerge given that the product is sold at the major supermarkets across the nation.

"We do expect to see more cases and I think that will happen throughout the country," she said on Monday.

Frozen berries grown in Chile, packaged in China, and distributed by Victorian based Patties have been linked to the infections.

Poor hygiene in a Chinese factory is likely the cause of contamination, University of Melbourne's microbiology expert Said Ajlouni says.

"If there is a sick employee in the company who went to the toilet, came back without appropriate washing of hands, he could have transferred the virus easily to the produce," Dr Ajlouni told AAP.

"One single employee could cause the problem, because these viruses can be spread very easily."

He said it was possible, but less likely, that water or soil caused the contamination because viruses lay dormant until they reach a human or animal.

Hepatitis A is spread when traces of faecal matter containing the virus come in contact with hands, water or food and then enter a person's mouth.

Farmers are calling for an overhaul of labelling laws to prevent such outbreaks.

Victorian Farmers Federation president Peter Tuohey said Australian food producers had to meet strict growing, handling and quality assurance standards often not in place in countries behind imported foods.

"Our view would be to buy Australian grown and you're going to going to eat a safer, better quality product than imported," Mr Tuohey said.

"But quite often these imported products are packaged in a way that makes them look Australian made."

People who have eaten the suspect berries are being advised to look out for symptoms such as fever, chills, tiredness, abdominal pain, nausea and jaundice.

The virus has an average incubation period of 28 days but can range from 15 to 50 days.

Most people recover from it, however people with chronic liver issues are at risk of death.

AAP