Somewhere on the North Carolina State campus, a machine has been puking vanilla pudding. Aerosolized vomit-pudding sprays out of its mouth, which stretches open in permanent retching position. Unpleasant? Not as unpleasant as the real-life scenario the vomiting machine is testing: whether norovirus spreads through aerosolized human puke.
Bad news, the answer is probably yes, according to the vomiting machine researchers who published their results in PLoS ONE today. Norovirus causes 20 million cases of food poisoning in the US every year—usually on cruises and other confined spaces with cafeterias. The virus is highly contagious. Epidemiologists have long suspected that barfing sends the virus airborne, allowing it to land on new surfaces or, for the especially unlucky bystander, right in his or her mouth. Gross, but very convenient for a virus that causes puking.
The NC State researchers spent two years building and then testing a miniature version of the upper digestive tract—essentially a tube (esophagus) connected to a pressurized chamber (stomach). Then they mixed together fake saliva, fake vomit aka vanilla pudding, and a real virus. Norovirus itself is too dangerous to work with, so they used a bacteriophage harmless to humans called MS2. The machine heaved this mixture into a chamber, and a device vacuumed out any aerosolized particles for analysis.
In a worst case scenario, a single puking episode aerosolized as many as 13,000 virus particles. And it only takes 20 to 1,300 virus particles to get someone sick. So be considerate when you puke, okay?
