The ward has been closed at least three times before in similar circumstances, and several hospitals in both Otago and Southland are also managing Covid-positive patients.
There were 39 people in the region in hospital who had Covid-19 yesterday, down slightly from 43 on Sunday.
A Te Whatu Ora Southern spokeswoman said visiting had been suspended immediately for the ward, and that all necessary steps were being taken to ensure the exposure events were contained.
"This includes closely monitoring patients for signs and symptoms of Covid-19 and influenza, and ensuring our staff are well when they come to work.
"Our priority is patient safety, and we apologise for the inconvenience to patients in the ATR Ward and and their families."
Yesterday, the national seven-day rolling average of people in hospital with Covid-19 was 799. A week ago it was 768.
A further 395 new cases of Covid-19 were reported in Otago and Southland yesterday, from a national total of 5312.
There were a further 28 deaths reported of people who had Covid-19, one of whom was from Southern.
Active cases in the South dipped below 4000 yesterday, to 3871.
A week ago, almost 5000 people in the region had Covid-19.
