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Vladimir Fedorenko via Wikimedia Commons // CC-BY-SA 3.0

How TB Grew Stronger and Spread Wider with the Collapse of the USSR

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Vladimir Fedorenko via Wikimedia Commons // CC-BY-SA 3.0

A new study published in the Proceedings of the National Academy of Sciences has found that the USSR’s breakup and subsequent turmoil allowed one strain of tuberculosis to evolve in a virulent, drug-resistant form that continues to plague Central Asia. They also traced the spread of the strain from Central Asia to Afghanistan and then to Europe due to armed conflict and population displacement. 

Every action we take has unpredictable consequences on the world around us, and geopolitical events are no different. With this fact in mind, an international team of anthropologists and disease experts set out to investigate if and how human history could have altered the evolution of one widespread human disease.

Alain Grillet/ Sanofi Pasteur via Flickr Creative Commons // CC BY-ND 2.0

The tuberculosis-causing bacterium (Mycobacterium tuberculosis complex, or MBTC) exists in seven distinct subtypes, or lineages. The second, third, and fourth lineages have been wildly successful as diseases go, but exactly how they’ve done it remains the subject of some disagreement. For this study, the researchers focused on the second lineage (L2), the so-called "Beijing lineage," a particularly nasty strain that’s rapidly spreading and shows drug resistance.

The team collected samples of L2 tuberculosis germs from patients in Europe, South Asia, and Central Asia. They scanned all the bacterial genes in order to sort out the geographic origins of each patient’s TB, as well as to pinpoint the moments in the disease’s evolution when specific mutations—like those that make it resistant to medication—first appeared.

Their results indicated that one especially drug-resistant subtype of L2 was most common in former Soviet states. This would make plenty of sense if the mutations conferring drug resistance had evolved while the states were all part of the same Soviet Union. But the mutations are relatively new. They evolved in those places after the Soviet Union collapsed—a time of intense and violent conflict. On top of that, citizens of these states were being displaced en masse, and public health resources were nearly nonexistent.

The strain has spread as a consequence of armed conflict and population displacement, the authors write. It was introduced to Afghanistan with the 1979–1989 Soviet invasion and occupation. It spread further after the American invasion in 2001, when much of the population experienced further upheavals. L2 continued to mutate in Afghanistan, creating a new strain. More recently it's been detected in Europe in small TB breakouts mostly limited to Afghan refugees.

The authors say the combination of these factors may have created a perfect environment in which TB could grow, get tougher, and become more virulent. Drug-resistant TB continues to be a major health concern in Central Asia. “Our results highlight the detrimental effects of political instability and population displacement on global TB control,” they write, “and demonstrate the power of [these] methods for understanding bacterial evolution in time and space.”

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This Living Wallpaper Uses Bacteria to Generate Electricity
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Previously known as the culprit behind some of the worst eyesores in home decorating history, wallpaper may be on the verge of a comeback. As FastCoDesign reports, scientists at Imperial College in London, the University of Cambridge, and Central Saint Martins have pioneered an innovative wall covering made of paper that contains live bacteria. The goal? To use that bacteria to generate electricity.

Here’s how it works. The paper is processed through a common inkjet printer, getting stamped with both conductive ink and then cyanobacteria, a photosynthesizing organism that gathers energy from light sources and turns it into electricity. After being exposed to the light, the paper's ink is able to conduct energy from the bacteria. The sample used—paper roughly the size of an iPad—powered a small LED bulb and digital clock via energy collected over the course of 100 hours.

Researchers at Imperial and their colleagues at the University of Cambridge and Central Saint Martins say the applications for “living wallpaper” are numerous. It could be used to monitor indoor air quality by powering sensors; in health care settings, small samples could monitor patients with conditions like diabetes. If enough energy could be harvested, it might be able to power larger devices or even charge phones—all of it disposable and biodegradable.

The project will next attempt to scale the paper panels up in size to allow for greater photosynthesis productivity while cleverly disguised as home decoration.

[h/t FastCoDesign]

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Dirty Money: The Cash In Your Wallet Is a Magnet for Germs
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If an item is handled by the public, whether it's a library book, a subway pole, or an ATM, you can count on it being filthy. One of the worst offenders is something most people carry around wherever they go: money. As TIME reports, a new study confirms that paper money is a magnet for germs and other microorganisms.

For their paper, which appears in the journal PLOS One, researchers swabbed dozens of $1 bills collected from New York City banks over the course of 2013. The results showed microbes from numerous sources living within the fibers. Most came from the human body, like skin bacteria, oral bacteria, and even vaginal bacteria. But non-human DNA was also prevalent. In the summer, researchers were most likely to find traces from pets like dogs and horses, while microbes from indoor fungi were more common in the winter. Skin break out lately? The bacteria to blame for acne were the most common microorganisms detected.

That list alone is enough to make you feel squeamish when leafing through your wallet, but it doesn't end there. American paper currency is 75 percent cotton and 25 percent linen; this composition makes it a cozy environment for other microorganisms like viruses. According to SmartMoney, the flu can survive on paper money for more than 10 days under the right conditions. E. coli and salmonella have also been detected on paper bills.

While these facts make a good case for washing your hands after each transaction, there's no reason to make the full switch to plastic. The same properties that make money such a good home for bacteria also make it hard to spread those germs to people. When microbes settle into the woven material of a dollar, they tend to stay there, even when you take it out and pass it to someone else. And if some microbes do rub off on you, your skin does a great job of keeping them from getting inside your body where they can do real harm. But you should still remember to use hand sanitizer before eating that burger you just paid for.

Unfortunately, objects touched by strangers aren't the only germ-infested environments to be aware of. Here are some of the dirtiest surfaces lurking in your home.

[h/t TIME]

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