Officials are scrambling to stop the spread of norovirus on the eve of the PyeongChang Winter Olympic Games.
According to Olympics organisers, the norovirus spread began on Sunday when private security workers staying near PyeongChang started complaining of headaches, stomach pain and diarrhea.
About 1,200 people were kept in their rooms during tests for the contagious virus.
Local and national health officials say they have investigated 1,023 people. Games organisers said on Wednesday that 32 workers are being treated for norovirus and are in quarantine, including three foreigners.
Because the sick workers handled security, 900 military personnel have been brought in to work at 20 venues until the sick and sequestered can return to work.
A preliminary five-day survey of water for cooking and drinking has come up negative for norovirus. Health officials say they are also inspecting restaurants and all food facilities linked to the Olympics.
Despite the official response, South Koreans have criticized the allegedly poor preparations at the Olympics, and what they believe was a slow reaction to initial reports of the virus.
Local media have reported that the first symptoms began on January 31 – not Sunday, as organisers say.
There have been reports of bad hygiene at the accommodations and complaints about meals and lodgings.
A local newspaper published an interview with an anonymous civil security staff member who said that the tap water at the facility that accommodated the security workers “smelled fishy, or like something was decaying.”
