A national salmonella outbreak has widened with at least 15 Queenslanders now infected after consuming frozen microwave meals.

Health officials have issued an urgent recall of Core Powerfoods meals which have tested positive to salmonella in Queensland, Victoria and South Australia.

A Core Powerfoods meal.

Nationally, 38 cases of salmonella Weltevreden have been diagnosed, forcing the recall of eight varieties with Best Before dated from March 5 to October 10, 2020.

People have been urged people to check their freezers for the recalled products.