Infection Control
What this domain tests
Infection Control tests the chain of infection, standard and transmission-based precautions, hand hygiene, sterilization, and healthcare-associated infection prevention.
Core rules
- Chain: infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, susceptible host. Break any link to prevent transmission.
- Standard precautions apply to all patients: hand hygiene, gloves, gown, mask, eye protection based on exposure risk, and safe injection practices.
- Contact precautions for MRSA, VRE, C. difficile, and scabies; droplet for influenza, pertussis, and meningococcus; airborne for tuberculosis, measles, and varicella.
- C. difficile requires soap and water because alcohol does not kill spores.
- Sterilization destroys all microorganisms including spores; disinfection reduces pathogens on inanimate objects but may not kill spores.
- Hand hygiene is the single most effective measure; use alcohol-based rub for routine decontamination and soap and water when hands are visibly soiled or after C. difficile care.
Worked example
A patient has new watery diarrhea and is confirmed C. difficile positive. What precautions? Reasoning: place on contact precautions in a private room if possible, wear gloves and gown for every entry, and wash hands with soap and water after contact. Alcohol rub does not reliably inactivate spores. Clean shared equipment with a sporicidal agent and dedicate equipment where feasible.
Traps
- Using alcohol rub after caring for a patient with C. difficile.
- Assuming gloves replace hand hygiene.
- Applying airborne precautions to all respiratory infections.
- Removing personal protective equipment in the wrong order, contaminating skin or clothing.