Since the 1940s, when penicillin was made available for medical use, antibiotics have made major contributions to public health. 1 Just to name some, antimicrobial therapies (including antibiotics) have markedly decreased the burden of infectious diseases (e.g. pneumonia and tuberculosis) and have allowed the introduction of complex medical interventions such as major surgery, organ transplantations and care of premature babies, by preventing hospital-acquired infections.