Besides supporting direct care of patients, diagnostic tests can also be used to characterize and monitor infectious agents, resistance trends and transmission episodes in the form of surveillance systems which can help limit the further spread and emergence of resistant bacteria.
Antibiotic resistance surveillance systems generate essential information and are a valuable tool for governments, hospital stewardship programs and healthcare systems in general. This information is also used to measure and anticipate resistance trends in order to assist research and development efforts in the creation of new antibiotics and diagnostics. As well, the spatial and temporal evolution of an infectious agent, along with its pattern of resistance to antibiotics, determines the public health measures to be taken in order to avoid dangerous outbreaks.
To track resistant bacteria, several countries have set up monitoring programs, which vary widely in their scope (healthy animals, diseased animals, food, healthy humans, sick humans) and also in their focus (Staphylococcus aureus, Clostridium difficile, Salmonella, Campylobacter, Escherichia coli, Enterococcus, animal pathogens, etc.). For instance, the UK boasts a successful example of such a surveillance system, which contributed to understanding and curbing MRSA and C. difficile infections in hospitals.(44)
Many countries have not yet set up such monitoring programs, especially in low-resource settings.(45) A comprehensive global network based on harmonized surveillance protocols is still an unrealized dream. Currently, data related to antibiotic resistance have to be viewed with caution as they may vary considerably between studies and countries, depending on the methods and computational models used.