Scientists Record High-Speed Imagery of Snot Rockets

These high-speed images of sneezes will make you never want to leave the house without a pack of tissues again. In the journal Experiments in Fluids, a group of MIT scientists who study the ways infections spread through snot sprays report that sneezes aren’t as simple as we thought. Rather, mucus ejects from our mouths and noses in “a complex cascade of events from sheets, to bag bursts, to ligaments, which finally break into droplets,” they write. 

The researchers recorded the sneezes of three people using two high-speed cameras (6000 to 8000 frames per second). They tickled the subjects' noses, then took images of 100 sneezes.

They found that the droplets of saliva and mucus don’t spray ready-made from our bodies. Instead, the liquid emerges from your face in thick sheets that expand with your breath—kind of like your sneeze is blowing up a snot balloon. From there, the mucus-saliva mixture goes through a quick succession of shapes, becoming long, thin filaments before forming airborne droplets. Bigger droplets fall to the ground, while the smaller droplets remain suspended in a “turbulent cloud” of potentially infectious snot.

“We expected to see droplets coming out fully formed from the respiratory tract,” one of the study’s authors, MIT assistant professor Lydia Bourouiba, explains in a press release. "It turns out that’s not the case at all.” To their surprise, snot droplets aren’t uniform.

And some people spray differently than others. People with more elastic snot shot liquid filaments farther into the air than other sneezers, whose snot broke into droplets earlier. This might mean that some people are more likely to spread germs than others through their sneezes.

Bourouiba is creating a new lab to study the way infectious diseases spread through droplets, especially the common cold and the flu. In addition to studying how diseases spread through the environment, she also hopes to be able to identify people who are “super spreaders.” She has previously studied how coughs spread infectious drops through the air.

All images from the paper, “Visualization of sneeze ejecta: steps of fluid fragmentation leading to respiratory droplets,” by B. E. Scharfman, A. H. Techet, J. W. M. Bush, L. Bourouiba.

Canine Flu is On the Rise: Here's What You Should Know

It's been eight years since the World Health Organization announced the end of the swine flu pandemic, and now the condition is back in the news for infecting a different type of host. As Live Science reports, the H1N1 virus is mixing with canine flu to create new strains that could potentially spread to people.

Dog flu has been around for a couple of decades, but the two main canine strains, H3N8 and H3N2, have never been contracted by humans. According to a new study published in mBio, some dogs in the Guangxi region of China were found carrying H1N1, the flu strain at the root of the swine flu outbreak. Researchers also discovered three entirely new flu strains that were a combination of H1N1 and regular dog flu viruses.

The unrecognized flu strains are the most troubling discovery. As the flu travels between species, it mingles with viruses that are already there, creating a level of genetic diversity that leaves our immune systems, which are best equipped to fight strains they've already been exposed to, vulnerable. The swine flu epidemic of 2009 started in a similar way, when H1N1 jumped from birds to pigs, and eventually to people.

But the new report isn't a reason to banish your pet to the doghouse next time she seems under the weather. The virus samples were collected from dogs in China between 2013 and 2015, and in the years since, zero humans have caught influenza from dogs (though dog flu has started spreading to cats). If the virus continues mutating to the point where it can infect humans, both the CDC and U.S. Department of Agriculture will take action. But for now, the CDC states that canine flu viruses "pose a low threat to people."

Canine flu may not be dangerous to humans yet, but it can still be stressful for dog owners if their pet comes down with a case. Ask your vet about getting your dog vaccinated, and if you see your dog coughing, sneezing, and acting less energetic than usual, make an appointment to get him checked out as soon as possible. If he does have the flu, he can be treated with plenty of rest and hydration.

[h/t Live Science]

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3 Simple Ways to Stay Tick-Free This Summer

As the weather gets warmer, you no doubt want to don your favorite shorts and get out in the sunshine. Unfortunately, shorts season coincides with tick season, and we're in the midst of what one expert calls a "tick explosion."

Tick expert Thomas Mather of the University of Rhode Island told Boston 25 News that warm weather is going to lead to a particularly bad summer for ticks. The blood-sucking bugs aren't just annoying—they spread Lyme disease and several other serious illnesses, including a pathogen that can cause a sudden allergy to meat.

There are several precautions you should take to stay safe from ticks and the risks they carry during the high season, which usually lasts from April to September, though some ticks can stay active year-round as long as it's above freezing. While ticks usually live in grassy or wooded areas, you should be careful even if you live in the city, because pathogen-spreading ticks can still be hiding in urban parks.

Tick prevention begins when you get dressed. Wear long sleeves and pants, and if you're in a tick-prone area, tuck your pants into your socks to better protect your legs. Opt for light colored clothing, because it's easier to see bugs against a light color versus a dark one.

You'll want to invest in insect repellent, too, for both you and your pets. The CDC recommends treating your clothing (and tents, and any outdoor gear) with permethrin, an insecticide that you can apply to fabric that will last through several washes. Permethrin not only repels ticks, but kills them if they do manage to get onto your clothes, and you can buy socks and other clothing that come pre-treated with it. Insect repellents with DEET are also effective against ticks.

Since ticks are most likely to make their way onto your feet and ankles, make sure to treat your shoes and socks. And since your dog is more likely to get a tick than you are, make sure to get Fido a tick collar or some other kind of tick medication.

Most of all, you just need to stay vigilant. When you come inside from the outdoors, check your body for any ticks that may have latched on. Ticks can be as small as a poppyseed, so make sure to look closely, or ask someone else to check hard-to-see places like your back. And since they like moist areas, don’t forget to give your armpits and groin a careful look. If you do catch a tick, remove it as soon as you can with a pair of tweezers.

Best of luck out there.


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