Nursing clinical group leader Katherine Martin said Student Health had been out to all of the university's residential colleges to vaccinate newly returned students, and was running extra clinics in the evening depending on the demand.
While the number of students wanting vaccinations remained about the same, the flu season itself was changing, Ms Martin said.
"In the last few years, the flu season has shifted. Peak flu season has shifted to late July and into August."
Student Health acting director Margaret Perley said over the past few weeks the service had seen an increase in students "presenting with flu-like illnesses"."This is common at this time of year, when students have returned to university following the mid-year break.
"Having an annual flu vaccination together with good hand hygiene, staying away from others when unwell and maintaining a healthy immune system remains the best protection against influenza."
In June, a shortage of vaccines led to the prioritisation of pregnant women; people with certain chronic illnesses; children aged 4 and under with severe respiratory illness; those aged 65 and over; and people with severe asthma, heart disease, diabetes and other serious health conditions which made them more susceptible to flu.
However, after 55,000 more vaccines were introduced into the country in early July, students were eligible again, Ms Martin said.
The Southern District Health Board area was experiencing a high rate of flu, compared with other areas of the South Island.
According to the ESR measure, 46 out of every 100,000 visits in the week ending July 21 were related to an influenza-like illness, compared with 27 in the South Canterbury DHB area, 42 in the Canterbury area, 13 in the Nelson-Marlborough area and 17 in the West Coast area.
