Just days after a deadly listeria outbreak in a New Zealand hospital was made public, some 40 patients at three health facilities supplied by North Shore Hospital’s kitchen have been hit by a stomach infection.

The outbreak was not related to the listeria outbreak reported in Hawkes Bay last week.

Errol Kiong a spokesman for North Shore Hospital, told the New Zealand Herald that Auckland Regional Public Health Service staff were trying to identify the reason for the outbreak, adding, "We think it may be related to food somehow. We don’t have any confirmation on that. The reason we think it’s food is because the supply chain for all three areas is from the same place. The food is prepared at North Shore Hospital."