CLOSE

The Puking Robot That Helps Scientists Study Infectious Noroviruses


Wikimedia Commons

Norovirus might be the perfect human pathogen. It hacks our DNA to create new noroviruses, gives us diarrhea, makes us puke so that the virus can spread to new hosts—and it spreads like wildfire. More than 1.1 million people in Britain have been infected so far this winter. According to the Centers for Disease Control and Prevention (CDC), norovirus causes 21 million illnesses annually in the United States. Approximately 70,000 require hospitalization and around 800 die each year.

Norovirus first appeared in Norwalk, Ohio, in November 1968, but how the virus gets into our cells still isn't well understood. "It’s not even clear exactly which type of cell they invade once they reach the gut," Carl Zimmer writes at National Geographic. “Regardless of the type, they clearly know how to exploit their hosts. Noroviruses come roaring out of the infected cells in vast numbers. And then they come roaring out of the body. Within a day of infection, noroviruses have rewired our digestive system so that stuff comes flying out from both ends.”

The viruses, says Zimmer, alter our intestinal lining and cause the cells to dump fluids, which contain many noroviruses (5 billion per gram of feces, in fact). And they make us repeatedly projectile vomit by tapping into our nervous systems and making our nerves send signals that will quickly contract the muscle lining of the stomach. Again, how these viruses do it is a mystery, but some studies have shown that during a norovirus infection, the digestion of food is slowed down. “In other words,” Zimmer says, “they seem to load up the stomach in preparation for vomiting.” Once outside the body, the viruses float through the air and end up on counters, food, and any other surface you can think of. On hard surfaces, they can survive 12 hours; on contaminated fabrics, 12 days. They also survive freezing, heating, and bleaching.

According to Zimmer, scientists don’t have a good way to study noroviruses, because they haven’t figured out how to rear them in human cells in a lab environment. But they can look at how the viruses spread—and that’s where Vomiting Larry comes in.

Larry is a humanoid robot that projectile vomits puke laced with a fluorescent marker. This allows scientists at the Health and Safety Laboratory in Derbyshire, England, to study how far particles of vomit travel, become aerosolized, spread, and infect others. “That’s important,” says Maggie Koerth-Baker at BoingBoing (where the above video comes from), “because it explains one of the ways that viruses spread by vomiting manage to end up in everyday things like, say, frozen raspberries. Aerosolized vomit isn't something you can spot. It doesn't clean up easily. And even just a drop of it can pass on plenty of viruses.”

Right now, scientists have Larry rigged up to study noroviruses, which Ian Goodfellow, a professor of virology at the department of pathology at Britain's University of Cambridge, told Reuters is “one of the most infectious viruses of man. It takes fewer than 20 virus particles to infect someone. So each droplet of vomit or gram of feces from an infected person can contain enough virus to infect more than 100,000 people." Using Larry, they've determined that aerosolized vomit can travel about 10 feet away from the puker.

So what’s the easiest way to stay healthy? Use common sense: Avoid anyone with the symptoms of the virus, wash your hands with warm, soapy water (Goodfellow suggests counting to 15), and dry your hands thoroughly.

nextArticle.image_alt|e
arrow
History
The Queen of Code: Remembering Grace Hopper
By Lynn Gilbert, CC BY-SA 4.0, Wikimedia Commons

Grace Hopper was a computing pioneer. She coined the term "computer bug" after finding a moth stuck inside Harvard's Mark II computer in 1947 (which in turn led to the term "debug," meaning solving problems in computer code). She did the foundational work that led to the COBOL programming language, used in mission-critical computing systems for decades (including today). She worked in World War II using very early computers to help end the war. When she retired from the U.S. Navy at age 79, she was the oldest active-duty commissioned officer in the service. Hopper, who was born on this day in 1906, is a hero of computing and a brilliant role model, but not many people know her story.

In this short documentary from FiveThirtyEight, directed by Gillian Jacobs, we learned about Grace Hopper from several biographers, archival photographs, and footage of her speaking in her later years. If you've never heard of Grace Hopper, or you're even vaguely interested in the history of computing or women in computing, this is a must-watch:

nextArticle.image_alt|e
iStock
arrow
science
Why Are Glaciers Blue?
iStock
iStock

The bright azure blue sported by many glaciers is one of nature's most stunning hues. But how does it happen, when the snow we see is usually white? As Joe Hanson of It's Okay to Be Smart explains in the video below, the snow and ice we see mostly looks white, cloudy, or clear because all of the visible light striking its surface is reflected back to us. But glaciers have a totally different structure—their many layers of tightly compressed snow means light has to travel much further, and is scattered many times throughout the depths. As the light bounces around, the light at the red and yellow end of the spectrum gets absorbed thanks to the vibrations of the water molecules inside the ice, leaving only blue and green light behind. For the details of exactly why that happens, check out Hanson's trip to Alaska's beautiful (and endangered) Mendenhall Glacier below.

[h/t The Kid Should See This]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios