One person has died and two people have been hospitalised with listeria in Tauranga, prompting a warning to pregnant women and others at risk.
Public health authorities say the person who died had an underlying health condition and all three were over 70.
The disease can be dangerous for unborn or newborn babies, the elderly or those with poor immunity.
The Ministry of Primary Industries compliance director Gary Orr is looking into whether a common food source is to blame.
