Nosocomial infections cause considerable morbidity and mortality. Healthcare workers (HCWs) may serve as vectors of many infectious diseases, many of which are not often primarily considered as healthcare-associated. The probability of pathogen transmission to patients depends on several factors, such as the characteristics of a pathogen, HCW and patient. Pathogens with high transmission potential from HCWs to patients include norovirus, respiratory infections, measles and influenza. In contrast, human immunodeficiency virus (HIV) and viral hepatitis are unlikely to be transferred. The prevention of HCW-associated transmission of pathogens include systematic vaccinations towards preventable diseases, continuous education, hand hygiene surveillance, active feedback and adequate staff resources.