A viral video from Japan aims to show how easily germs and viruses can spread in restaurants when just one person is infected. The experiment simulates the atmosphere at a buffet restaurant or on a cruise ship. It was conducted by the public broadcasting organization NHK in conjunction with health experts.
The video shows 10 people coming into the restaurant, with one singled out as an "infected" person. A fluorescent substance only visible under black light is applied onto that person's hands, representing germs from a cough or a sneeze.
Each participant then goes about the buffet as they normally would, not considering a potential contamination. Over the course of a typical dining period, the rest of the guests behave in predictable fashion, selecting utensils from serving stations, enjoying their food, checking their phones and so on.
At the end of the video, the participants are cast under black lights illuminating where the "infection" has spread. The substance, used to signify the germs, can be seen on food, serving utensils and platters, and even on the faces of some of the participants.
NHK also did a second experiment where the simulated environment anticipated contamination and put in the necessary precautions. All of the participants, including the "infected" person, washed their hands before and during eating. Frequently touched surfaces, such as serving utensils, were replaced or wiped down.
When the participants went under the black light, none of the substance from the "infected" person had spread to the other participants.
"What the video demonstrated, is that it will spread to surfaces and to people very efficiently," John Nicholls, a clinical professor in pathology at Hong Kong University told CNN. However, Nicholls said that the situation is "artificial" because there was so much fluorescent liquid on the "infected" person's hands that it wouldn't accurately reflect the amount of germs on someone's hands.
"The experiment just described the possibility of the spread by contact, and that is not proof of what happened," Kentaro Iwata, an infectious disease specialist at Kobe University told CNN.
But both experts said the experiment is a good way to show the importance of hand washing and hygiene.