nosokomial

Nosocomial infections, also called hospital-acquired infections, are infections that patients acquire during a stay in a healthcare facility and that were not present or incubating at the time of admission. They can occur in hospitals, clinics, or long‑term care settings and are a major concern for patient safety and infection control.

Common types include bloodstream infections, urinary tract infections associated with catheter use, pneumonia (including ventilator-associated pneumonia), and surgical site infections. The pathogens involved vary by setting but frequently include Staphylococcus aureus (including MRSA), Escherichia coli and other Enterobacterales, Pseudomonas aeruginosa, Acinetobacter species, Enterococcus species, and Candida species.

Transmission typically occurs through the hands of healthcare workers, contaminated surfaces or equipment, and invasive devices such as catheters and ventilators. Patient-related risk factors include older age, underlying chronic disease, immune suppression, prolonged hospital stay, prior antibiotic exposure, and the use of invasive devices.

Prevention focuses on multiple complementary strategies: rigorous hand hygiene, adherence to aseptic technique, appropriate use and care of invasive devices, environmental cleaning and disinfection, antibiotic stewardship to limit resistance, and rapid identification and isolation of infected patients when needed. Surveillance programs track rates of HAIs, provide feedback to healthcare facilities, and help guide policy; examples include national surveillance networks and international guidelines.

The burden of nosocomial infections includes longer hospital stays, higher treatment costs, and increased patient morbidity and mortality, varying by country, facility type, and patient population. The term remains widely used, though healthcare-associated infection is increasingly employed in modern practice.