Nature reports that medical experts are concerned that if antibiotic overuse in hospitals is not curbed, drug-resistant strains of the Acinetobacter baumannii bacterium could become a serious killer in intensive-care wards worldwide.

“We have calculated that 40% of our patients who become infected with A. baumannii die because of it,” says Yehuda Carmeli, an infectious-disease physician at the Tel Aviv Sourasky Medical Center in Israel.