Pyeongchang Winter Olympics organizers said on Monday a total of 177 norovirus cases had been confirmed so far at the games but that the athletic delegations remained unaffected.

They said 19 new cases of the virus, which causes vomiting and diarrhea, had been confirmed as of Sunday afternoon.

The organizers added added that of the 177 cases, 68 had recovered and had been released from quarantine and returned to work at the games

The virus had broken out in the leadup to the opening ceremony in Pyeongchang last Friday and led to some 1,200 security staff being quarantined. Organizers had to call in military personnel to replace them.

No athletes have been confirmed to have contracted the highly contagious virus. An outbreak at last year’s World Athletics Championship in London forced competitors from several countries to miss events.

Pyeongchang Winter Olympics organizers has said several agencies were cooperating to stifle the outbreak, with water quality being tested and inspections taking place at venues, restaurants, hotels and worker accommodations.