A fourth frozen berry product has been recalled in the wake of a spate of cases of hepatitis A linked to produce sourced in China.

Nanna's raspberries one-kilogram packs are being withdrawn by Patties Foods as a precautionary measure, days after the company recalled the Nanna's and Creative Gourmet brands of mixed berries.

Twelve people — five in Queensland, three in Victoria, and four in New South Wales — have become sick with hepatitis A after eating Nanna's frozen mixed berries.

The company's managing director, Steven Chaur, said there were no tests linking the product to hepatitis A.

"Investigations through our supply chain have identified a specific source of raspberries as a potential common link to the possible safety issues raised by health authorities," he said.

"The specific source supplied raspberries which were packed in Nanna's and Creative Gourmet Mixed Berries, that were the subject of the consumer recall announced over the weekend."

Mr Chaur said scientific tests into the berries were ongoing.

"We are sending samples internationally to be tested for this virus to identify whether there is actually a link between hepatitis A and our products, but in the meantime our number one priority is public safety," he said.

Mr Chaur apologised to consumers and said the company was "working proactively" with health authority investigations.

"The supplier of raspberries is no longer used by Patties Foods," he said.

"Some product that was previously supplied by the source may still be in the market and we are taking this added precautionary measure of conducting an additional consumer recall of all frozen raspberries associated with this specific source located in China, in the interests of public safety."

Poor hygiene among Chinese workers as well as potentially contaminated water supplies in China are thought to be the likely causes of the outbreak.

The recall of Nanna's raspberries one-kilogram packets relates to products with best before dates up until November 22, 2016.

Hepatitis A attacks the liver, causing jaundice, nausea and vomiting for up to eight weeks.

According to the World Health Organisation, the disease is primarily spread when an uninfected or unvaccinated person ingests food or water contaminated with the faeces of an infected person.

Concerned consumers can call Patties Foods on 1800 650 069.