Egypt's Health Ministry announced on Tuesday that cases of food poisoning of Azhar students have reached 479, confirming however that no deaths have been recorded to date.
An official told the state news agency on Monday that patients were transferred to several local hospitals to receive medical attention, adding that all cases are so far stable.
Hundreds of students of the Muslim world's most prestigious university had gathered in protest on Monday, blocking main roads and bringing traffic to a halt, to express anger over campus meals causing food poisoning.
Egypt's general prosecutor has ordered the formation of an expert team to investigate the case and the collection of random samples of the food that is being served to students, his spokesman said.
Prime Minister Hisham Kandil has said that he has been following up on the case since Monday night with Azhar Sheikh Ahmed al-Tayeb and the health minister.
Both Kandil and Tayeb have ordered concerned parties to begin investigating the incident to punish all those who are responsible in order to avoid similar incidents in the future.
Tens of students organized a protest by the Azhar campus early on Tuesday against the university president who has suspended some staff members, including the university's food director, from work.
A team from the health ministry is expected to arrive to campus later today to follow up on the health crisis.