Infection control is the application of evidence-based practices to prevent the transmission of infectious agents within healthcare settings. Healthcare-associated infections (HAIs) affect a substantial number of hospitalized patients each year and contribute to thousands of deaths, prolonged hospital stays, and major added cost. The encouraging reality is that the vast majority of HAIs are preventable through consistent application of standard and transmission-based precautions, hand hygiene, and device-specific prevention bundles. The chain of infection must be broken at any link to prevent transmission: 1. Infectious agent (pathogen — bacteria, virus, fungus, parasite, prion) 2. Reservoir (where the pathogen lives — human host, water, soil, equipment) 3. Portal of exit (how it leaves the reservoir — respiratory tract, blood, feces, wound drainage) 4. Mode of transmission (how it travels — contact, droplet, airborne, vehicle, vector) 5. Portal of entry (how it enters a new host — mucous membranes, broken skin, respiratory tract, GI tract) 6. Susceptible host (compromised immunity, invasive devices, immunosuppression) Infection control in practice: The nurse's primary role is to break the chain, particularly at link 4 (mode of transmission)...