Oyster imports on hold after fans get ill

Korean oysters are off the menu temporarily as the country's food watchdog reviews their import.

The New Zealand Food Safety Authority (NZFSA) has suspended imports of the oysters after dozens of corporate patrons at the All Blacks-Irish test at Eden Park last month reported becoming ill.

Tests found the norovirus bug was present in South Korean oysters served at the match. New Zealand oysters tested negative for the virus.

The authority is reminding people not to eat uncooked oysters from Korea and said packets of the frozen oysters were clearly labelled as needing to be cooked under their import health standard.

The NZFSA has come under pressure from the New Zealand shellfish industry to block their import outright, but executive director Andrew McKenzie said that was probably not going to happen.

"We export to countries and also import so it's just a balancing act in those things. We are principled in the way we treat other countries."

He said the authority had temporarily "lost confidence" in the certification of the oysters which said they were grown in clean water.

It was not the first time the oysters had made people in New Zealand sick.

A review of shellfish import standards was under way as part of the authority's major food review.

"We've stopped imports while we go through that process," Mr McKenzie said.

One reason for continuing imports of the oysters was that they cost $1 a kg. The home-grown varieties could cost four times that.

Norovirus is a highly infectious gut virus that can spread from person to person through vomiting or touch, or through eating contaminated food.