Ayo-Yusuf said the cafeteria had been closed until the investigation was completed.
"Counselling and psycho-social support services will be organised for both Hunadi Magongoa's classmates, her friends and football teammates," said Ayo-Yusuf.
He urged students and staff to "remain calm during this painful period" and to allow time for the investigation to determine if there was a link between Magongoa's death and the food she had at the cafeteria.
In the interim, students presenting with any symptoms such as diarrhoea, abdominal cramps, fatigue, weight loss and nausea are being assisted at the campus health clinic or the Dr George Mukhari Hospital, he said.
So far, about 75 students have been examined and discharged from the campus clinic.