Listeria has been found in a supermarket salad.
All LeaderBrand salads have now been recalled, despite the food-borne bacteria being found only in the Caesar Salad.
The company said it has recalled its entire salad product range, including LeaderBrand Classic Salads, Fresh Plus Salads, Value Bag Salads, Pam's Fresh Express salads and 100 per cent Fresh Salads from the major supermarkets it supplies.
Countdown, New World and Pak'n Save stock the salads. All salad products distributed to Pita Pit and Subway outlets have also been recalled.
A spokesman for Subway said they were unaffected but were withdrawing lettuce and carrot from their stores as a precaution.
Customers were urged not to eat any of the salads bought since March 3 with a best-before date earlier than March 18.
LeaderBrand chief executive Richard Burke said the company learned of the contamination yesterday.
"While LeaderBrand Caesar Salad is only one of many product lines - and we are confident none of our other products have been affected - we immediately took steps to withdraw all salad products," he said.
"We emphasise that this is an isolated incident and that as a proudly New Zealand owned and operated company, we take the health and safety of our customers very seriously. As things stand, we anticipate being able to supply fresh salad products soon. We thank you for your understanding and apologise for any inconvenience caused."
People who bought the salads can return them for a refund.
The Ministry for Primary Industries (MPI) said that it was working to support LeaderBrand with the recall.
"LeaderBrand are collaborating with MPI to effectively manage the situation by removing product from sale and informing consumers.
"The ministry is working with the company to determine the source of the contamination and put in place actions to prevent future occurrences."
Listeria is a bacteria commonly found in soil and water and some animals. It can grow at refrigeration temperatures.
It can be particularly harmful to vulnerable people, including children under 5, adults over 65, pregnant women and people with compromised immune systems.