An outbreak of norovirus has spread amongst security guards at the 2018 Winter Olympics in Pyeongchang, South Korea, with dozens taken to hospital.

1,200 of the security guards have been withdrawn from Olympic sites, with 900 soldiers and military personnel replacing them. On Sunday, many security staff fell ill from the outbreak, and the number of people affected by norovirus continues to rise. At least 34 new cases have come from the Horeb Youth Centre, where the security personnel have been quarantined.

Spokesman for the Games, Christophe Dubi, said that all areas are being disinfected and that measures have been put in place to avoid a further outbreak of the highly contagious virus. Stringent measures are in place when it comes to food and beverages, he stated.

The case isn’t the first in recent memory where close contact with contaminated objects or surfaces has led to norovirus outbreaks at sporting events. At the 2017 World Athletics Championships in London, several athletes had to pull out of competition when an outbreak began at a local hotel.