New Zealand officials are on alert following a hepatitis scare in Australia, involving imported frozen berries.

Three Queenslanders have now tested positive for Hepatitis A after eating frozen berries.

New Zealand supermarket chains Foodstuffs and Countdown say they don't stock the brand of frozen berries that have potentially caused the contamination in Australia.

But the Ministry for Primary Industries says officials are still monitoring the situation and looking into all sources of imported frozen berries in case there's cause for concern.