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A cigarette sits in an ashtray. Smokers may be at greater risk of MRSA, a new study suggests. (AP Photo/Darron Cummings)
Superbugs such as MRSA are already bad enough. But it turns out that something can make them even nastier: cigarette smoke. Researchers found that antibiotic-resistant bacteria exposed to the smoke became more aggressive and far more difficult to kill, they explain at Eureka Alert.
It's almost as if the smoke sets off an alarm that causes the bacteria to strengthen its defenses, explains the Union-Tribune of San Diego. Scientists made the discovery by exposing immune cells to two different batches of MRSA, one normal and one treated with cigarette smoke extract.
The bigger the dose of smoke, the bigger the effect, notes Medical Daily. "We already know that smoking cigarettes harms human respiratory and immune cells, and now we've shown that, on the flipside, smoke can also stress out invasive bacteria and make them more aggressive," says lead author Laura Crotty Alexander of UC San Diego.
It's a double-whammy: Smokers already have weakened immune systems that make them more susceptible to infectious diseases, and the smoke they inhale seems to make invading pathogens even more dangerous.
In this study, the smoke helped MRSA survive longer and kill more mice with pneumonia. (The latest antibiotic-resistant bug to make headlines is a nasty stomach virus.)
This article originally appeared on Newser: Cigarette Smoke Makes Superbugs Even Stronger
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