pyeongchang security
A delegation of 32 people from North Korea arriving at the Gangneung Olympic Village for the Pyeongchange games. More than 1,000 people have been quarantined for a norovirus outbreak. Jeon Heon-Kyun-Pool/Getty Images

Security staff fell ill with the norovirus just days before the opening ceremony of the 2018 Winter Olympics were scheduled to officially kick off the games in Pyeongchang, South Korea.

More than 1,000 people have been quarantined and more than 40 were sick with the virus, The Washington Post reported. The country sent hundreds of soldiers to replace the security staff that fell ill. Most of the security guards who had the virus were staying at the youth center for the Olympics, said the Post.

The Korean Centers for Disease Control said it was investigating the cause of the outbreak in a press release. This includes interviewing those who are sick and looking into the ground water, the food and the food preparation. A test of the water at the youth center came back negative for the virus.

The games are happening just south of the border with North Korea and security has been incredibly high for those arriving at the games.

What is norovirus?

Norovirus causes the inflammation of the stomach or intestines and results in nausea, stomach pain, diarrhea, and throwing up, sometimes these symptoms are also accompanied by body aches, headache or fever. The illness usually lasts anywhere from one to three days and can lead to rapid and serious dehydration, according to the Centers for Disease Control.

The virus is highly contagious and due to the fact that there are many versions of it, people can get it several times in their life. It can be transmitted through coming in contact with food or liquids, surfaces or people who have the virus or recently had the virus, according to the CDC. The tight quarters and massive number of people who gather for the Olympics makes it easy for the virus to spread quickly.

There is no treatment for norovirus other than rest and hydration to replace the lost liquids.