Shigella is a particularly nasty bacteria that causes Shigellosis, a form of food poisoning featuring bloody diarrhea, painful cramps and rectal spasms, and kills perhaps 1.1 million people per year. Yesterday, the Centers for Disease Control issued a warning in which they said international travelers have brought in a new form of the bacteria, and it's spreading within the US. This form features "multidrug resistance," and shows significant strength against Ciprofloxacin, the previous pharmaceutical go-to for drug-resistant Shigella.
In the CDC release, Director Tom Frieden urged caution, not just because this form of Shigella is harder to treat, but because "Shigella spreads so easily between people [that] the potential for more—and larger—outbreaks is a real concern." The outbreak of food poisoning a few years ago that temporarily shut down a Los Angeles-area Souplantation was caused by Shigella.
The CDC issued a comprehensive warning to the public about drug-resistant bacteria back in 2013. In that info-dump, they included Shigella on the list of potential threats, since it was already resistant to "first-line" drugs like ampicillin and trimethoprim-sulfamethoxazole, and just beginning to show signs of Ciprofloxacin-resistance. Since then, the threat of drug-resistant bacteria has stubbornly refused to go away, and Shigella has only become better at fighting off Ciprofloxacin.
As we've pointed out in the past, in the long run, people living today are likely under a greater threat of dying from drug-resistant bacteria than from cancer. While Shigellosis is generally more of a serious bummer than a death sentence, this still isn't just some vague future threat; a potentially deadly form of drug-resistant malaria currently endangers millions in East Asia, for example. Meanwhile, in the US, P. aeruginosa, the bacteria responsible for one out of every ten hospital-acquired infections, was discovered to have not just a drug resistant form in the usual sense, but the new form had acquired "super-resistance," making it able to withstand perhaps every antibiotic we know of.
Frieden added in the release that the CDC is "moving quickly to implement a national strategy to curb antibiotic resistance." Over the past few years, science has indeed discovered new evolutionary mechanisms in bacteria that make them able to adapt to our defenses more quickly than we imagined, and discovered that treating someone with antibiotics might trigger one of those mechanisms. According to many microbiologists, fighting drug resistance means a long-term, complex solution, and we can start by curbing the rampant use of antibiotics in agriculture.
The CDC has been coy about blaming the farming sector for pumping antibiotics into livestock, but a 2013 report did acknowledge the agriculture connection. This particular infection is less related to farming practices than other bacteria, since non-human animals rarely acquire Shigella, according to the World Health Organization. But different species of bacteria appear to "learn" antibiotic resistance from each other, much in the way we humans would spread a hilarious new internet meme, via a process called horizontal gene transfer.
You can probably guess how to keep from getting infected with this germ, but just in case you need a primer on basic sanitation: Wash your own hands, and wash the hands of any children you happen to have around, particularly right before you eat or prepare food, and try not to go drinking any pond water.
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