Cross‑Infection Prevention: Core Principles for Healthcare Settings

Standard Precautions & Transmission‑Based Measures

Preventing pathogen transmission requires a layered approach. The Chain of Infection (pathogen → reservoir → portal of exit → mode of transmission → portal of entry → susceptible host) must be broken at multiple points.

1. Hand Hygiene (Single Most Effective)

• Alcohol‑based hand rub (ABHR) 60‑95% alcohol – preferred for most situations.
• Soap & water: visibly soiled hands, C. difficile, norovirus, Bacillus anthracis.
• 5 moments: before patient contact, before aseptic task, after body fluid exposure, after patient contact, after patient surroundings.

2. Personal Protective Equipment (PPE)

• Gloves: contact with blood, body fluids, mucous membranes, non‑intact skin.
• Gowns: anticipated soiling of clothing.
• Masks + eye protection / face shield: splash/spray risk.
• Respirators (N95+): airborne precautions (TB, measles, COVID‑19, varicella).
• Don/doff sequence critical; train & audit.

3. Aseptic vs. Clean Technique

• Aseptic: Sterile field, sterile instruments, no‑touch technique (central lines, surgery, urinary catheter).
• Clean: Non‑sterile gloves, clean equipment (peripheral IV, wound dressing changes).

4. Safe Injection & Device Practices

• One needle, one syringe, one patient, one time.
• Single‑dose vials preferred; multi‑dose vials dedicated to single patient.
• Safety‑engineered devices (retractable needles, blunt suture).

5. Environmental Cleaning & Disinfection

• High‑touch surfaces: EPA‑registered disinfectant, contact time observed.
• Terminal cleaning after discharge/transfer.
• Terminal cleaning of OR/procedure rooms per protocol.
• Ventilation: ≥6 ACH (patient rooms), ≥12 ACH (OR); HEPA for airborne isolation.

6. Transmission‑Based Precautions (Added to Standard)

• Contact: MDROs, C. diff, norovirus, scabies – gown/glove on entry.
• Droplet: Influenza, pertussis, meningococcal – mask within 6 ft.
• Airborne: TB, measles, varicella, disseminated zoster – negative pressure room, N95+.

7. Isolation & Cohorting

Single room preferred; cohort same pathogen if single rooms unavailable.

8. Immunization

HCW: annual flu, Hep B, MMR, varicella, Tdap, COVID‑19 per CDC. Patients: offer vaccines per ACIP.

9. Waste Management

• Segregation: regulated medical waste (red bag), sharps, chemo, pharmaceutical, general.
• PPE for handlers; autoclave/incineration per state regs.

10. Education, Surveillance & Antibiotic Stewardship

• Ongoing competency training.
• HAI tracking (CLABSI, CAUTI, SSI, CDI, MRSA bacteremia).
• Antimicrobial stewardship program (ASP) mandatory.

Bundle implementation reduces HAIs 30‑70%. Leadership commitment essential.