HAIs represent a significant burden in terms of morbidity, mortality and cost worldwide. They lead to longer hospital stays, a three-fold risk of death and a 300% increase in the cost of hospital care. In the EU, it has been estimated that five million patients acquire a HAI each year with an average of one percent of these cases ending in death (around 50,000 deaths). In France, the overall direct extra cost has been estimated at around one billion euros per year. The increasing involvement in HAIs of multiple drug-resistant strains of emerging and re-emerging infectious agents further complicates this situation.
Currently, a wide range of control strategies is already available, including hygiene measures, barrier precautions, antimicrobial stewardship, vaccination, patient isolation, cohorting, etc., based on screening programmes and surveillance systems.
Also, several previously published modelling studies were réalised but they were typically limited to describing one of these scales, separately from the others.
Healthcare-associated infections (HAIs) are infections declared at least 48 hours after admission of the patient. They can acquire a new infection due to contact with infected individuals or hospital environment.
Despite significant progress in infection control, a lot remains to be done. This stems notably from the (re)emergence of virulent infectious agents with the ability to spread in healthcare settings, including multi-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) or Enterobacteriaceae with increasing levels of resistance to cephalosporins or carbapenem (CRE), viruses coming from the community such as Influenza, and new emerging threats generated by worldwide exchanges such as SARS, MERS-CoV or Ebola.