Auckland’s active cluster, which emerged on February 14, expanded to 11 community cases on Tuesday.
It now includes Papatoetoe High School pupils and a sibling of a pupil who works at KMart and recently attended the high school.
The university said yesterday it was calling students who arrived from South Auckland in the past 14 days, asking about their recent movements and general health status.
On social media it told students with links to Papatoetoe High School, or anyone who had been to any of the places of interest identified by the Ministry of Health, to contact Public Health or HealthLine, and to stay in their college, flat, or homestay until they had done so.
Any students with symptoms consistent with Covid-19 should get a test, it said.
A university spokesman said the statement was issued after discussions with Southern District Health Board medical officer of health Dr Susan Jack.
Dr Jack confirmed yesterday there was "a small number" of students who had been tested and were now self-isolating following ministry guidance.
Since students started arriving for the academic school year this month, neither the university nor the health board have been able to provide the total number of students who travelled from Auckland to start the year in the city.
"It is too early to say how many students may be affected by this," Dr Jack said yesterday.
The university earlier said about 650 first-year students from Auckland arrived in Dunedin for the start of the academic year.
Others returning from Auckland who were not living in university-owned residential halls were advised at the time to follow ministry guidelines for preventing the spread of Covid-19.
O Week, an orientation programme which features nightly sold out gatherings of students, is under way.