Initially, the flu season in the South was quiet, with the region registering about half the national average of flu-like illness presentations in the latest weekly ESR monitoring report, to July 15.
However, that had changed in the past week or so, particularly among young people.
Dr Maiai said the centre was busier than the previous two winters.
The influenza A strain (H3N2) prevalent in Christchurch had been identified in Dunedin.
The clinic was coping but students were having to wait a week for a routine appointment instead of the usual two or three days.
Otago and Southland medical officer of health Dr Marion Poore said surveillance data from general practices showed an increase in flu-like illness in the past week.
"This is not surprising, as typically we start to see this pattern of illness in late July.
"Teenagers and young adults are the age group most affected at present and we're aware that Student Health Services in Dunedin have seen a large number of patients."
Some patients had been admitted to Dunedin Hospital, but as of yesterday morning there were none in intensive care.
George Street Normal School had about 60 pupils absent yesterday, principal Rod Galloway said. About 50 did not attend the start of school, while another 10 or so "faded" throughout the day. The school has 437 pupils.
Mr Galloway said the fever, sore throat, and sneezing bug seemed to be lingering longer this year.
However, pupil absences at St Clair School and Tahuna Normal Intermediate, in Dunedin, were modest yesterday.
Dunedin North Medical Practice nurse Theresa Hurring said the health centre was still quiet flu-wise, but many patients were "utterly miserable" with colds. However, now the season was picking up she recommended people get their flu jab before it was too late.
The Southern DHB barely registered for confirmed flu viruses in the weekly update to July 15, with just a handful of confirmed influenza A viruses this year, compared with about 450 in Canterbury.
In a press release yesterday, Health Minister Tony Ryall said officials were carefully monitoring the flu season.
"New Zealand is now well and truly into the winter flu season and the latest information from the Ministry of Health is that the number and timing of people presenting with flu is not abnormal.
"Last winter was a particularly quiet year for flu."
Mr Ryall said the Ministry of Health was extending the flu vaccine scheme for eligible people for an extra month, to the end of August.
Strains identified so far this year were covered by the vaccine, he said.