© iStockphoto.com/Brett_Lamb
The
vomit machine! ow do scientists study the
virus Collaborative for Outreach, Research,
to reflect different stages of digestion. A
transmission of viruses
and Education).
bacteriophage called MS2 — a virus that
from person to person?
To test the theory, researchers in Jaykus’s
Why, with a vomit ma-
lab needed a controlled way to observe and
chine of course!
study vomiting over and over again. They
Norovirus is a group of
needed a vomiting machine.
infects E. coli but is harmless to humans — was substituted for norovirus. After extensive testing of the machine, they began using it for formal experiments, which showed that the virus was indeed
more than 30 related viruses that can cause
Unsurprisingly, a vomiting machine is
vomiting and diarrhoea, with infections
not something that can be found on eBay,
sometimes requiring hospitalisation and
so the researchers had to design and build
And although the amount of MS2 aero-
occasionally causing death in vulnerable
their own. A graduate student from the civil,
solised as a percentage of total virus ‘vom-
groups such as the elderly.
aerosolised.
construction and environmental engineering
ited’ was relatively low (less than 0.3%),
About a quarter of ‘noro’ infections are
department provided the construction know-
vomit from infected people contains millions
obtained by consuming contaminated foods
how, while data on vomiting was provided
of particles, meaning the actual amount of
or water, but it is most often spread between
by a gastroenterologist.
virus particles aerosolised during a single
people in close contact with each other.
Working together, the researchers created
vomiting event ranges from only a few into the thousands, perhaps more.
A long-held theory is that norovirus can
a machine that is essentially a scaled-down
be ‘aerosolised’ through vomiting, meaning
version of the mouth, oesophagus and
“And that is enough to be problematic
that small particles containing norovirus can
stomach — made of tubes and a pressure
because it only takes a few, perhaps less
become airborne when someone throws up,
chamber that passes through a clay face
than 20, to make a susceptible person ill,”
transmitting directly to a nearby person or
to give it the correct vomiting angle. The
Jaykus said. “This machine may seem odd,
contaminating surfaces. (Fun fact: Noro
machine is designed to let researchers
but it’s helping us understand a disease that
can still be detected in dried vomit after
control the pressure and volume of the
affects millions of people. This is work that
six weeks.)
vomit, in order to mimic a range of natural
can help us prevent or contain the spread
But norovirus aerosolisation by vomiting
vomiting behaviours. The device is enclosed
of norovirus — and there’s nothing odd
had never been proven. Enter norovirus
in a sealed Plexiglas box and placed under
about that.”
expert Lee-Ann Jaykus, a professor of food
a biosafety hood.
science at North Carolina State University
Liquid solutions of different viscosities or
and scientific director of NoroCORE (Noro-
thicknesses were used as ‘artificial vomitus’
38 | PREPARED FOOD - Dec 2015/Jan 2016
The research was published in the PLOS ONE journal.
www.preparedfood.com.au