ABSTRACT
Definitions Healthcare-associated infection (HAI or ‘nosocomial’ infection) is an infection occurring >48 h after admission to hospital, or within a defined period after healthcare contact. HAI can be endogenous (from the patient’s own microbial flora) or exogenous (transmitted from another patient, member of staff, or the hospital environment). The latter is known as cross-infection. An outbreak is three or more related cases of HAI. Surveillance is an ongoing systematic collection of HAI data with analysis, interpretation and reporting.
