Swiss health authorities have ordered a quarantine for 2,500 students at a prestigious hospitality management school in the city of Lausanne after “significant outbreaks” of Covid-19 that are a suspected byproduct of off-campus partying.

Authorities in Switzerland’s Vaud canton, or region, said all undergraduates at the Ecole Hoteliere de Lausanne, known as the Lausanne Hospitality Management University in English, had been ordered to quarantine both on and off-campus because the number of outbreaks “made a more targeted closure impossible”.

“The earliest elements of an investigation indicate that the organisation of one or more parties was at the origin of these many outbreaks of infection,” the Vaud regional office said in a statement, adding that the parties seemed to take place before new containment measures in the region were announced on September 15.

School administrators were taking “all necessary measures” to ensure that classes were continuing online, the statement said.

University spokesman Sherif Mamdouh said on Thursday that 11 students had tested positive for the coronavirus and none required hospitalisation.

Mamdouh said the quarantine affects 2,500 undergraduates. The university has around 3,500 students. He said hundreds of students living in campus dormitories would be subject to the quarantine.