When the first antibiotics were discovered in the early 20th century, the rate of death from infectious diseases fell dramatically. But the emergence of multidrug-resistant bacteria as a result of antibiotic misuse is raising fears that by 2050, these same diseases will once again become the leading cause of death worldwide. In a bid to boost the arsenal available to tackle this threat, scientists from the Institut Pasteur, the CNRS and the Universidad Politécnica de Madrid successfully programmed a bacterial genetic structure to make it capable of specifically killing multiple antibiotic-resistant bacteria without also destroying bacteria that are beneficial to the body. Unlike other approaches under development, this novel tool is associated with a minimal rate of emergence of new resistance. The results were published in the journal Nature Biotechnology on April 15, 2019.