Winter Olympics' security felled by norovirus

At last report there were 194 confirmed cases of norovirus at the Pyeongchang Winter Olympics. So far no athletes have been affected but 107 of those affected have been security personnel housed at the Horeb Youth Center. In response, Games organisers have withdrawn more than 1200 security guards from their duties and replaced them with 900 soldiers.

Norovirus is the most common cause of gastroenteritis globally. It is reputed to cause 685 million cases of disease and 200,000 deaths each year. It is a regular, if unwelcome, guest on many cruise ships. Fewer than 20 virus particles can cause an infection and eradication is not easy.

The virus is typically spread through physical contact or the ingestion of contaminated food or water. Transmission can be aerosolised when those with the illness vomit or flush the toilet after vomiting or an episode of diarrhoea. Even breathing air or eating food in an area after vomit has been cleaned up can result in infection. To make matters worse, sufferers can remain contagious for several days after they are symptom-free.

Korean health authorities investigating the origin of the virus initially suspected cooking with ground water, contaminated food handlers and consumption of contaminated food products. The MFDA and the Ministry of Environment conducted an initial investigation of the water at the youth centre over the course of five days, and tests came back negative for norovirus.

The South Korean government has distributed thousands of bottles of hand sanitisers to help stem the outbreak but alcohol-based hand sanitisers are not particularly effective in preventing infection. The Pyeongchang organising committee (POCOG) has designated a supervisor to monitor daily cleaning of Olympic venues and apartments where athletes, organisers and media are staying.

The Korea Centres for Disease Control and Prevention (KCDC) is continuing to monitor the situation and is reporting that the rate of new infections is slowing down.