We hope to be cured when we stay in hospital. But too often, we acquire new infections there. Such ‘healthcare-associated infections’ (HAI) are a growing problem worldwide, taking up an estimated 6% of global hospital budgets. In the EU alone, HAIs add up to more than 3.5 million cases per year, resulting in 2.5 million disability-adjusted life years, a cost of up to €24 billion, and 90,000 deaths. They are likewise the sixth leading cause of death in the US.
Patients with lowered immune defenses, and in some hospitals, poor adherence to hygiene protocols, allow HAIs to thrive. Furthermore, antibiotics are widely used in hospitals, which tends to select for hardy, resistant strains of bacteria. When such resistance genes lie on mobile genetic elements, they can even jump between bacterial species,…