Hospital infections, animal models and alternatives.

Bacteria represent a threat to human health, especially in healthcare settings, and treatment options are limited due to increasingly common antibiotic resistance. It is, therefore, imperative that we continue to investigate the mechanisms of pathogenesis and host-pathogen interactions. Despite the fact that some bacterial pathogens are capable of infecting both humans and at least one laboratory animal species, the relevance and animal welfare implications of animal infection models are of concern. Here, we consider whether plants and lower organisms are suitable candidates to investigate certain aspects of bacterial pathogenicity. Indeed, many of the virulence factors employed by micro-organisms render the capacity to infect a range of hosts. The scope for using such models, together with 3D human "organoids", to accelerate the development and screening of novel drugs and treatment combinations for bacterial infections is considered.