By Katie Todd of RNZ.
At least two people who have tested positive for Covid-19 went to the Wanaka A&P show this month.
The show on 13 March was an optional stop-off for about 300 guests from the World Hereford Conference in Queenstown, four of them have now tested positive for the virus.
Conference delegates came from New Zealand, Australia, Europe, South Africa, North and South America and visited the Millennium Hotel in Queenstown and two central Otago stations, as well as the A&P show.
Health authorities have been trying to trace all of them, since confirming the cases yesterday, but say there is a low risk of close contact for about 40,000 other A&P show guests, meaning they do not have to self-isolate if they do not have any symptoms.