(NBC News) Doctors rely on antibiotics to destroy the bacteria that make patients sick, everything from ear infections in kids to life-threatening bloodstream infections.
But there's a caveat.
"The more we use antibiotics, the more resistant the bacteria become," explains Dr. Steve Solomon of the Centers for Disease Control.
Among the most urgent threat in this country is CRE, also known as "nightmare bacteria". It's found primarily in hospitalized patients who've already received antibiotics to treat other infections.
"The danger now is that these resistant bacteria which are in hospitals, especially in intensive care units, will begin to spread to other patients in the hospital and even outside the hospital," Dr. Solomon explains.
That happened with another bacteria called MRSA, originally only found in hospitals but now common in the community and difficult to control. Experts say doctors need to prescribe antibiotics cautiously and patients have a duty to take them as directed. That means finishing the entire course of medication even if you feel better because it helps ensure all of the bacteria are killed.
The World Health Organization has now declared antibiotic resistance an immediate, global health threat.
Other bacteria that have emerged as resistant include salmonella and the sexually transmitted disease gonorrhea, an infection that left untreated can lead to serious complications, including infertility.
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