Vomit machine shows diseases can be shared in the air

RALEIGH, N.C., Aug. 20 (UPI) -- Researchers created a "vomit machine" to discover whether people can be infected with norovirus if they directly or indirectly come in contact with a sick person's vomit. Thanks to their on-demand wretching experiments, they now know the answer is yes.

It has been thought that norovirus can be aerosolized in vomit but not proven, even though it can be detected in dried vomit after 6 weeks.

"This machine may seem odd, but it's helping us understand a disease that affects millions of people," said Lee-Ann Jaykus, a professor of food science at North Carolina State University, in a press release. "This is work that can help us prevent or contain the spread of norovirus -- and there's nothing odd about that."

The researchers created a model version of the mouth, esophagus and stomach using a pressure chamber and tubes that pass through a clay face, which allows for the angle of vomit to be adjusted. The face is inside a large box so researchers can see where projectile vomit lands once it's ejected from the body.

Using fake vomit and the bacteriophage MS2, a common stand-in for norovirus in lab experiments because it does not infect humans, the researchers found that norovirus is aerosolized in vomit more than enough to infect other people.

In the lab, MS2 was less than 0.3 percent of vomit, but the millions of virus particles that represents could infect thousands of people. It may take as few as 20 particles to infect somebody, Jaykus said.

The study is published in PLOS ONE.