Healthcare-associated infection

Healthcare-associated infections are defined as infections that occur in a patient during the process of care in a hospital or other healthcare facility, which were not present or incubating at the time of admission. They include infections acquired in acute-care hospitals, outpatient settings, long-term care facilities, and home care. The most common types are catheter-associated urinary tract infections, central line-associated bloodstream infections, surgical site infections, and ventilator-associated pneumonia.¹ These infections are often caused by multidrug-resistant organisms, complicating treatment and increasing mortality.

HAIs are caused by a wide range of bacteria, fungi, and viruses, with bacteria being the most common. Transmission occurs through direct contact with contaminated hands, surfaces, or equipment, as well as through airborne droplets and invasive devices. The use of indwelling devices, such as urinary catheters and central venous catheters, bypasses natural barriers and provides a portal for pathogens.² Immunocompromised patients, the elderly, and those in intensive care units are at highest risk. The emergence of antibiotic-resistant organisms, such as MRSA and Clostridioides difficile, has made prevention and treatment more challenging.

Prevention of HAIs relies on a combination of infection control practices, including hand hygiene, environmental cleaning, and the appropriate use of personal protective equipment. Evidence-based bundles for catheter insertion and maintenance have significantly reduced central line-associated bloodstream infections and ventilator-associated pneumonia.³ Antimicrobial stewardship programs help reduce the development of resistance. Surveillance systems, such as the National Healthcare Safety Network, allow facilities to track and benchmark infection rates, guiding quality improvement efforts.⁴ Vaccination of healthcare workers and patients also plays a role in preventing transmissible infections.

Beyond the well-known hospital-acquired infections, HAIs also occur in outpatient settings, such as dialysis centers and ambulatory surgery centers, where surveillance is less standardized. The term "healthcare-associated" also includes infections in healthcare workers, such as needlestick injuries leading to hepatitis B or HIV. The COVID-19 pandemic highlighted the risk of airborne transmission in healthcare settings, leading to enhanced ventilation and respiratory protection guidelines.⁵ Additionally, the microbiome of the hospital environment, including sink drains and ice machines, can serve as reservoirs for resistant pathogens. The economic burden extends beyond direct costs, including lost productivity and increased length of stay, which are often underestimated.

Nosocomial

Originating in a hospital; hospital-acquired.

MRSA

Methicillin-resistant Staphylococcus aureus, a common resistant pathogen.

Bundle

A set of evidence-based practices used together to improve patient outcomes.