GC107 Protect Yourself And Your Patients
GC107 Protect Yourself And Your Patients is a General Medical Council good clinical care guidance topic emphasizing infection control, safe practices, and risk management to safeguard both healthcare professionals and patients from harm.
Protect Yourself and Your Patients – Infection Control Perspective
The Big Idea: Every healthcare worker (HCW) is simultaneously a potential victim of infection from patients and a potential vector carrying pathogens to patients. This lecture, delivered by Clinical Microbiologist Dr. Vincent Cheng (QMH), lays out the practical framework that breaks both directions of that chain. It is organized around three pillars: (1) Hand hygiene, (2) Transmission-based precautions (Contact / Droplet / Airborne), and (3) Prevention of blood-borne pathogen exposure (sharps safety and post-exposure prophylaxis).
Why this matters for exams: Infection control is tested in MCQs (e.g. "Which precaution for TB?"), SAQs (e.g. "Steps after a needlestick injury"), minicases, and OSCEs (hand hygiene technique, PPE donning/doffing). The topic cross-links with GC 061 (HIV/needle prick), GC 098 (antibiotic prophylaxis), GC 102 (immunocompromised host), GC 104 (infection outbreak), and GC 100 (defense against microbes).
Learning objectives (inferred from slide structure):
- Understand the historical context and rationale for infection control (SARS 2003).
- Master the WHO 5 (+1) Moments of Hand Hygiene and the six-step technique.
- Know when to use soap-and-water vs. alcohol-based handrub (ABHR).
- Classify infections by transmission route and select the correct transmission-based precautions.
- Prevent blood-borne pathogen transmission: barrier precautions, sharps safety, post-exposure prophylaxis (PEP).
- Know the immune-status inventory and vaccine-preventable diseases for HCWs.
1. Historical Context: Why Infection Control Is "A Matter of Life and Death"
SARS 2003: ~1700 cases in Hong Kong; HCWs comprised ~60% of nosocomial outbreak cases across multiple hospitals worldwide. [1]
- Index case: Male/53, relative of Guangzhou professor, admitted 25/2/03 — seeded Hotel Metropole → chains of transmission to hospitals in HK (KWH, QMH, PYH, PWH), Vietnam, Singapore, Canada, and elsewhere. [1]
- Koch's Postulates applied to SARS-CoV: isolation of filterable virus in pure culture, consistent positive RT-PCR from SARS patients with seroconversion, first-generation diagnostics (RT-PCR for viral genes, immunofluorescent test for antibodies). [1]
Infection control: a matter of life and death
Four named HK doctors died from SARS. The lecture specifically names Dr. Tse Yuen Man, Dr. Lau Tai Kwan (Paediatric Surgery), Dr. Cheung Sik Hin (ENT Surgery), and Dr. Cheng Ha Yan. This is to underscore that infection control failures kill healthcare workers — it is not merely a bureaucratic exercise. [1]
| Year | System | Key Feature |
|---|---|---|
| 1970 | 7 Isolation Precaution Categories | Disease-specific categories |
| 1983 | Category-specific / Disease-specific | Dual approach |
| 1985 | Universal Precautions (UP) | Treating all blood as infectious |
| 1987 | UP + Body Substance Isolation | Added all body substances |
| 1996 | Standard Precautions + Transmission-Based Precautions | Current system — the one you must know |
The 1996 CDC/HICPAC framework combining Standard Precautions with Transmission-Based Precautions is the current paradigm. [1]
Standard precautions apply to ALL patients, ALL the time, regardless of diagnosis. They exist because the potential for infectivity of any patient's blood and body fluids cannot be known. [1]
Standard precautions protect against transmission from:
- Blood
- All body fluids, secretions, excretions (except sweat), regardless of whether visible blood is present
- Non-intact skin
- Mucous membranes
Components of Standard Precautions [1][2]:
- Hand hygiene before and after every patient contact (including after glove removal)
- Gloves, gowns, eye protection when exposure to body secretions or blood is possible
- Safe disposal of sharps in impervious sharps containers
- Safe injection practices: aseptic field, single-use disposable needles/syringes, single-dose vials preferred
3. Hand Hygiene — The Single Most Important Infection Control Measure
Historical hand hygiene compliance in hospitals is typically < 40%. [1]
The lecture presents a table of compliance rates from 1981–1999 across ICUs, general wards, neonatal units, and emergency rooms. The range is 16–81%, with most studies clustered around 30–48%. This is a shocking indictment of HCW behavior and is why the WHO launched its "SAVE LIVES: Clean Your Hands" campaign.
Why compliance is low:
- Time pressure (perceived)
- Skin irritation from soap and water
- Inconvenient sink locations
- Low perceived risk ("my patient looks clean")
ABHR achieves a 3-log reduction in microbial load in 15 seconds, compared to only 0.8-log reduction with soap and water in the same time. [2]
Why ABHR is superior to soap-and-water for routine use:
- More effective bactericidal and virucidal activity
- More convenient — not limited by sink availability; can be carried in pocket, placed at point of care
- Better skin care — glycerol in WHO formulations acts as emollient
| Component | Formula I | Formula II |
|---|---|---|
| Active alcohol | Ethanol 80% v/v | Isopropyl alcohol 75% v/v |
| Emollient | Glycerol 1.45% v/v | Glycerol 1.45% v/v |
| Sporicidal additive | Hydrogen peroxide 0.125% v/v | Hydrogen peroxide 0.125% v/v |
Role of each component:
- Ethanol/Isopropanol (60–85%): The killing agent. Denatures proteins and dissolves lipid membranes of microorganisms.
- Glycerol: Prevents skin drying and cracking (cracked skin harbors more bacteria).
- Hydrogen peroxide (0.125%): Does NOT kill organisms on hands at this concentration. Its purpose is to inhibit growth of bacterial spores inside the bottle during storage. [2]
Alcohols are effective against vegetative bacteria, enveloped viruses, fungi, mycobacteria, and most non-enveloped viruses, but NOT against bacterial spores or prions. [1]
Descending order of resistance to germicidal chemicals (from most resistant to least):
| Rank | Organism Type | Alcohol Effective? |
|---|---|---|
| 1 | Prions | ❌ No |
| 2 | Bacterial spores | ❌ No |
| 3 | Protozoan oocysts (e.g. Cryptosporidium) | ❌ No |
| 4 | Mycobacteria | ✅ Yes |
| 5 | Non-enveloped viruses (e.g. Norovirus) | ⚠️ Variable* |
| 6 | Fungi | ✅ Yes |
| 7 | Vegetative bacteria | ✅ Yes |
| 8 | Enveloped viruses (e.g. Influenza, HIV, HBV) | ✅ Yes (most susceptible) |
Non-enveloped viruses are marked with ** on the slide — alcohol has reduced activity against some non-enveloped viruses (notably norovirus), hence why soap-and-water is preferred for C. difficile and norovirus outbreaks.
When to Use Soap-and-Water Instead of ABHR
Use soap and water (not ABHR) when: [1][2]
- Hands are visibly dirty/soiled with blood or body fluid
- After using the restroom/toilet
- Caring for patients with C. difficile infection (spores not killed by alcohol)
- Caring for patients with norovirus (non-enveloped virus, variable alcohol susceptibility)
Use ABHR for:
- All other clinical conditions when hands are NOT visibly soiled
- Before putting on sterile gloves
Apply 3 mL of ABHR and rub for at least 15–20 seconds (minimum 20 seconds for the six-step technique). [1]
The five WHO moments define WHEN to perform hand hygiene:
| Moment | When | Why |
|---|---|---|
| 1 | Before touching a patient | Prevent transferring community/hospital flora to patient |
| 2 | Before a clean/aseptic procedure | Prevent introducing organisms into sterile sites |
| 3 | After body fluid exposure risk | Protect yourself and environment from patient's organisms |
| 4 | After touching a patient | Prevent carrying patient's organisms to environment/next patient |
| 5 | After touching patient surroundings | Environment is contaminated — treat it as patient contact |
The 6th moment (QMH/HKWC addition): Before touching your own mucous membranes (e.g. rubbing your eyes, eating). [1]
Why the 6th moment matters: The lecture emphasizes that bacterial counts on HCW hands range from 3.9 × 10⁴ to 4.6 × 10⁶ CFU. The minimum infective dose of influenza via intranasal inoculation is only 127–320 TCID₅₀ (~100 PFU). So touching your nose/eyes with contaminated hands can easily transmit influenza. [1]
| Step | Action |
|---|---|
| 1 | Palm to palm |
| 2 | Palm to back of hand |
| 3 | Fingers interlaced |
| 4 | Back of fingers |
| 5 | Thumbs (rotational rubbing) |
| 6 | Fingertips (rotational rubbing into opposite palm) |
"Rub hands for at least 20 seconds" — displayed prominently in both English and Chinese on QMH infection control posters. [1]
NO RINGS. NO ARTIFICIAL NAILS. KEEP NAILS SHORT. [1]
Why:
- Rings create reservoirs underneath where organisms survive hand hygiene
- Artificial nails harbor more gram-negative organisms and fungi
- Long nails can puncture gloves and scratch patients
The lecture shows QMH compliance data (2017 2Q – 2019 1Q) trending over time, broken down by the 5 moments. This is to illustrate that ongoing audit and feedback is necessary to maintain compliance. The weakest moments are typically Moment 1 (before patient contact) and Moment 5 (after touching surroundings). [1]
4. Environmental Contamination and the "Exit & Entry Control" Concept
The lecture provides two comprehensive tables [1]:
Viral contamination of HCW hands:
| Pathogen | Hand contamination rate (%) | Survival on hand | Survival on inanimate surface |
|---|---|---|---|
| Influenza | NA | 10–15 min | 12–48 h |
| RSV | NA | < 20 min | 1–2 days |
| Adenovirus | NA | NA | 2 h – 60 days |
| SARS-CoV | NA | NA | 72–96 h |
| Rhinovirus | 19.5–78.6 | 2 h | 8 h – 12 days |
| Rotavirus | NA | 4 h | 6–60 days |
| Norovirus | NA | > 30 min | 7 days |
| HAV | NA | Several hours | NA |
| HBV | NA | NA | 7 days |
| HCV | 8–23.8 | NA | NA |
Bacterial contamination of HCW hands:
| Pathogen | Hand contamination rate (%) | Survival on hand | Survival on inanimate surface |
|---|---|---|---|
| S. aureus | 10.5–78.3 | > 150 min | 1–7 months |
| MRSA | 16.9 | NA | 1–7 months |
| VRE | 41 | 60 min | 5 days – 4 months |
| C. difficile | 14–59 | NA | 1 day – 5 months |
| E. coli | NA | 6–90 min | 2 h – 16 months |
| Klebsiella spp | 17 | 2 h | 2 h – 30 months |
| Acinetobacter spp | 3–15 | > 150 min | 3 days – 5 months |
| Pseudomonas spp | 1.3–25 | 30–80 min | 6 h – 16 months |
| Yeast | 23–81 | 1 h | 1–4 months |
Key Takeaway — Pathogens Survive MUCH Longer Than You Think
MRSA survives up to 7 months on inanimate surfaces. VRE survives up to 4 months. HBV survives 7 days on surfaces. This is why environmental cleansing and hand hygiene between patients are non-negotiable. [1]
A QMH study showed that in a 6-bedded cubicle, high-touch surfaces received up to 14 contact-episodes per hour per cubicle. Mutual-touch items (bed rails, call bells, overbed tables, IV poles) are constantly contaminated. [1]
92% of curtains showed contamination within 1 week: MRSA (21%), VRE (42%). [1]
This is a QMH innovation specifically targeting VRE and other MDROs:
A VRE-colonized patient produces up to 1 million VRE per gram of stool. Within 48–72 hours of admission, the patient's fingers and environment become heavily contaminated. [1]
Entry Control ("入口管制"): Directly Observed Hand Hygiene (DOHH) before taking meals and drugs
- Rationale: If a VRE-colonized patient takes a tablet with contaminated fingers, VRE goes straight into the GI tract, amplifies, and can cause clinical infection.
- The patient cleans hands with ABHR before eating or taking medications. [1]
Exit Control ("出口管制"): Personal hygiene in the toilet
Timeline of emerging MDROs: MRSA (1980s) → VRE (1990s) → ESBL (1990s) → Carbapenemases (2000s: KPC [Class A], OXA [Class D], IMP/VIM/NDM [Class B metallo-β-lactamase]) → Plasmid-mediated colistin resistance mcr-1 (2015). [1]
This progression is why infection control is escalating in importance — we are running out of antibiotics.
5. Transmission-Based Precautions
These are the second tier, added ON TOP of Standard Precautions for patients with documented or suspected highly transmissible pathogens. [1][2]
| Feature | Contact | Droplet | Airborne |
|---|---|---|---|
| Particle size | Direct/indirect touch | > 5 μm | < 5 μm (droplet nuclei) |
| Travel distance | Touch-dependent | ≤ 1 metre, falls quickly | Remains suspended; travels far |
| Room | Single room or cohorting | Single room or cohorting; ≥ 1 m between beds | Airborne Infection Isolation Room (AIIR) with negative pressure |
| HCW PPE | Gown + Gloves | Surgical mask (+ eye protection/face shield) | N95 respirator (fit-tested) + eye protection |
| Source control | — | Surgical mask on patient | Surgical mask on patient during transport |
Contact precautions are used for: MDR bacteria (MRSA, VRE, ESBL, CRE), Norovirus/Rotavirus, C. difficile, RSV, Parainfluenza, Enterovirus, highly contagious skin infections (e.g. scabies), viral hemorrhagic conjunctivitis, viral hemorrhagic infections. [1][2]
Contact Transmission can be:
- Direct: Body surface to body surface (e.g. bathing, turning the patient)
- Indirect: Via contaminated intermediate object (equipment, environmental surface, HCW hands) [1]
PPE for Contact Precautions:
- Gown AND gloves — don before entering the room, remove before leaving the room [1]
Patient Placement:
- Single room preferred; alternatively cohorting (placing patients with the same organism together) [1]
Dedicated equipment: Stethoscope, BP cuff, thermometer should NOT be shared between contact-precaution patients and non-isolated patients. [1]
Droplet precautions are used for: Influenza, Invasive H. influenzae type b, Invasive N. meningitidis, Diphtheria (pharyngeal), Adenovirus, Parvovirus B19, Mumps, Rubella, Mycoplasma pneumoniae, Streptococcal pharyngitis, Pertussis, Pneumonic plague. [1]
Key facts about droplets:
- Sneezing produces up to 40,000 droplets of 0.5–12 μm, expelled at 100 m/s. [1]
- Droplets are > 5 μm and do NOT remain suspended in air — they fall to the ground within 1–2 metres.
PPE for Droplet Precautions:
Patient Placement:
- Single room or cohorting; maintain ≥ 1 metre spatial separation [1]
Source Control: Place a surgical mask on the patient to reduce shedding of respiratory droplets during transport. [1]
Droplet vs. Airborne — The Key Discriminator
The critical exam distinction: Droplets ( > 5 μm) fall quickly, travel ≤ 1 m, and are blocked by surgical masks. Droplet nuclei ( < 5 μm) remain airborne, travel long distances via air currents, and require N95 respirators and negative-pressure rooms. If an MCQ asks about TB, measles, or varicella → always choose airborne precautions / N95 / AIIR.
Airborne precautions are used for: Mycobacterium tuberculosis, Varicella zoster, Measles (the classic triad: TB, VZV, Measles), plus Smallpox, COVID-19, SARS. [1][2]
Airborne Infection Isolation Room (AIIR):
- Negative pressure relative to corridor (air flows IN, not out)
- ≥ 12 air changes per hour (ACH) for new construction/renovation; ≥ 6 ACH for existing facilities [1]
- Air exhausted directly to the outside or recirculated through HEPA filtration [1]
- Anteroom between corridor and isolation room
- Doors kept closed [1]
PPE for Airborne Precautions:
- N95 respirator (NOT a surgical mask) + eye protection/face shield [1]
Fit Testing:
- Before initial use, a fit test must be performed to select the suitable type, model, and size for the individual. [1]
- Repeat fit testing is required if [1]:
- Significant weight change (~10% increase or decrease)
- Change in facial structure (dental work, cosmetic surgery, accident)
- Appropriate model/size no longer available
- Any condition interfering with face-piece sealing
Donning (6 steps) [1]:
- Place respirator in palm
- Position over nose, mouth, and chin
- Put headbands in place — avoid crisscrossing
- Seal nosepiece by pressing along nasal bridge
- Positive pressure test: Cover mask, exhale sharply — no air should leak from edges
- Negative pressure test: Cover mask, inhale sharply — mask should depress slightly inward; no air leak
Doffing (4 steps) [1]:
- Avoid touching the front of the respirator (contaminated surface)
- Tilt head forward, pull bottom headband over head with both hands
- Grab upper strap with both hands, keep tension as you remove it (lets mask fall forward without flipping inside out)
- Discard in waste container; perform hand hygiene
For suspected/confirmed Influenza A H7N9 or MERS: apply Standard + Contact + Droplet + Airborne precautions simultaneously. [1]
This is the maximum tier of precautions, reflecting initial uncertainty about transmission routes of novel pathogens.
6. Prevention of Blood-Borne Pathogen Transmission
HBV: up to 30%. HCV: up to 7%. HIV: 0.3%. [1]
Why is HBV risk so much higher?
1. Percutaneous (needlestick, sharps injury) — most common. 2. Mucous membrane exposure (splash to eyes/mouth). 3. Non-intact skin (dermatitis, abrasions, open wounds). [1]
6.3 Prevention of Exposure — Two Pillars
1. Appropriate barrier precautions. 2. Careful handling of sharps. [1]
| Situation | PPE Required | Why |
|---|---|---|
| Any invasive procedure involving a needle (venipuncture, phlebotomy, suturing) | Gloves | Reduces blood volume transferred if needlestick occurs through glove; double gloving further reduces inoculum |
| Splashing likely (arterial line insertion, wound irrigation, surgery) | Goggle + Mask + Protective gown | Protects mucous membranes and non-intact skin |
| HCW has a wound/cut | Cover wound with waterproof dressing before caring for patients | Prevents wound exposure to patient blood/body fluids |
Blood-taking setup [1]:
- Gloves
- Vacuum system (reduces open needle manipulation)
- Blue tray with small sharps box
- Retractable lancet and IV access with safety features (needle retracts after use)
- Safety scalpels (sterile disposable, blade retracts into handle)
Key rules:
- Never recap needles with two hands — use the one-hand scoop technique if recapping is absolutely necessary [1]
- Dispose of sharps immediately after use into puncture-resistant container
- Do not overfill sharps containers (max ¾ full)
- Use safety-engineered devices whenever available
QMH Percutaneous Injury Data (2016 2Q – 2019 1Q):
- Medical staff consistently highest number of needlestick injuries (10–22 per quarter), followed by nursing staff (4–15) [1]
- This reinforces why training on sharps safety is critical for medical students and junior doctors
Procedures following sharps injury [1]:
| Step | Action | Rationale |
|---|---|---|
| 1 | Staff sustains contaminated sharps injury or mucosal exposure | Recognize the event |
| 2 | Apply first aid on site — wash wound with soap and water; if mucosal exposure, irrigate with water/saline | Reduce inoculum; do NOT squeeze wound (increases blood flow into wound) |
| 3 | Report to ward in-charge | Chain of documentation and support |
| 4 | Attend Staff Clinic/A&E for blood screening + treatment (PEP) as required; complete incident report form | Time-sensitive for PEP |
| 5 | Send blood from source patient for HBsAg, HCV, HIV (with consent) | Determines what PEP is needed |
| 6 | Report "Injury on Duty" to Human Resources via AIRS | Occupational health documentation |
HIV PEP: Chemoprophylaxis after risk assessment. MOST EFFECTIVE within 2 hours of exposure. [1]
| Pathogen | PEP | Key Details |
|---|---|---|
| HIV | Antiretroviral chemoprophylaxis (typically 3-drug regimen for 28 days) | Must be started ASAP, ideally within 2 hours [1]; efficacy drops significantly after 72 hours |
| HBV | Depends on vaccination status: Responder (anti-HBs ≥ 10 mIU/mL) → no treatment needed. Non-responder → HBIG (± HBV vaccine series) | HBIG should be given within 24 hours, definitely not > 48 hours [3][4] |
| HCV | No PEP available | Monitor with baseline and follow-up HCV RNA; early treatment if seroconversion detected |
HIV PEP Timing Is Everything
Most effective within 2 hours post-exposure. Every hour of delay reduces efficacy. If a student sustains a needlestick from an HIV-positive patient at 2 AM, they should NOT wait until morning — attend A&E immediately. [1]
Free vaccination on 6 vaccine-preventable diseases for HCWs: [1]
- Hepatitis B
- Measles }
- Mumps } → given as MMR vaccine
- Rubella }
- Chickenpox (Varicella)
- Influenza A & B (annual)
Why each matters for HCWs:
- Hepatitis B: Highest occupational transmission risk (up to 30%); vaccine is 95% effective; anti-HBs ≥ 10 mIU/mL = protected
- Measles: Airborne transmission, highly contagious (R₀ ~ 12–18); non-immune HCWs can cause nosocomial outbreaks
- Mumps/Rubella: Part of MMR; rubella exposure in pregnant HCWs can cause congenital rubella syndrome
- Varicella: Airborne transmission; severe in immunocompromised patients; non-immune HCWs are a risk to patients
- Influenza: Annual vaccination because antigenic drift; HCWs are major vectors in hospital outbreaks
The Chain of Infection has 6 links. Break any link = prevent infection. [1]
Our interventions target specific links:
- Hand hygiene, PPE, environmental cleaning → break mode of transmission
- Isolation/cohorting → break reservoir (contain the source)
- Source control (mask on patient) → break portal of exit
- Vaccination, PEP → protect the susceptible host
- Antimicrobial stewardship → reduce emergence of resistant infectious agents
9. Special Topics — Integration with Related GC Lectures
The lecture references a UK nurse who died from community-acquired PVL-MRSA (Panton-Valentine Leukocidin). PVL is a pore-forming toxin that causes necrotizing pneumonia and severe skin infections. Key point: MRSA is not just a hospital problem — community strains carrying PVL can kill healthy young people. [1]
For immunocompromised patients (e.g. post-chemotherapy neutropenia, bone marrow transplant):
- Protective isolation with HEPA filtration (prevents Aspergillus)
- Low-microbe diet
- Face masks, hand hygiene by all entering the room
- Prevention of infections includes: screening for latent infections (HSV, CMV, HIV, HBV, Toxoplasma) before transplant [6]
Surgical antibiotic prophylaxis (e.g. cefazolin on induction) is a form of infection prevention for the patient. Key principle: give within 30 minutes of first incision, do NOT continue post-operatively (increases risk of C. difficile, resistance). [7]
GC 104 provides the theoretical framework; GC 107 is the practical application. Key overlaps include the transmission-based precautions taxonomy and PPE guidance. [2]
"Protect yourself first & your patient" [1]
This is the lecture's guiding philosophy. You cannot care for patients if you are sick. The order of priority:
- Personal protection: Vaccination, ABHR habit, N95 fit testing, sharps safety
- Patient protection: Hand hygiene between patients, appropriate isolation, environmental cleaning
- Institutional protection: Compliance monitoring, outbreak surveillance, antimicrobial stewardship
Likely Exam Questions
-
Which of the following infections requires airborne precautions?
- A. Influenza → Droplet
- B. MRSA colonization → Contact
- C. Pertussis → Droplet
- D. Measles → Airborne ✓
- E. Norovirus → Contact
-
After a needlestick injury from an HIV-positive source, what is the optimal time window for post-exposure prophylaxis?
- A. Within 24 hours
- B. Within 2 hours ✓
- C. Within 72 hours
- D. Within 1 week
-
Which of the following is NOT killed by alcohol-based handrub?
- A. MRSA
- B. C. difficile spores ✓
- C. Influenza virus
- D. HIV
-
A medical student sustains a needlestick injury while taking blood from a patient whose hepatitis B status is unknown. Describe the steps you would take. (6 marks)
- Apply first aid (wash with soap and water, do not squeeze) (1)
- Report to ward in-charge (1)
- Attend Staff Clinic/A&E for blood screening and PEP assessment (1)
- Send source patient blood for HBsAg, anti-HCV, anti-HIV (with consent) (1)
- Check own vaccination status: if anti-HBs ≥ 10 → reassure; if non-responder → give HBIG (1)
- Report Injury on Duty to HR via AIRS (1)
-
List 5 components of Standard Precautions. (5 marks)
- Hand hygiene before and after every patient contact (1)
- Gloves, gowns, eye protection when exposure to body fluids possible (1)
- Safe disposal of sharps in impervious containers (1)
- Safe injection practices (single-use needles, aseptic technique) (1)
- Respiratory hygiene/cough etiquette (1)
-
Explain why alcohol-based handrub is preferred over soap and water for routine hand hygiene in clinical settings. State two situations where soap and water must be used instead. (4 marks)
- ABHR: 3-log reduction in 15 seconds vs. 0.8-log for soap-and-water (1); more convenient (1); better skin care (glycerol) (1)
- Soap-and-water required: visibly soiled hands / after toilet use / C. difficile / norovirus (any 2 for 1 mark)
High Yield Summary
Standard Precautions apply to ALL patients: hand hygiene, gloves/gown/eye protection for body fluid exposure, sharps safety, safe injection practices. Transmission-Based Precautions are added for specific pathogens: Contact (MRSA, VRE, C. diff, norovirus → gown + gloves), Droplet (influenza, pertussis, meningococcus → surgical mask within 1 m), Airborne (TB, measles, varicella → N95 + negative-pressure AIIR). ABHR is superior to soap-and-water except when hands are visibly soiled, after toilet use, or for spore-forming organisms. WHO 5+1 Moments define when to clean hands. Blood-borne pathogen prevention: HBV risk up to 30%, HCV 7%, HIV 0.3% per needlestick. Post-exposure: first aid → report → Staff Clinic/A&E → source patient bloods → PEP (HIV within 2 hours; HBV non-responder → HBIG). HCW vaccination: Hep B, MMR, Varicella, Influenza. N95 requires fit testing; repeat if weight changes ≥ 10% or facial structure changes. Always remember: Protect yourself first, then your patient.
Active Recall - Lecture Notes
[1] Lecture slides: GC 107. Protect yourself and your patients.pdf (all pages cited throughout) [2] Lecture slides: GC 104. Infection outbreak_infection control [Handout].pdf (pages 5, 7, 8) [3] Senior notes: MBBS Final MB (Medicine) (Felix PY Lai).pdf (pages 754, 1069) [4] Senior notes: Ryan Ho GI.pdf (page 231) [5] Lecture slides: GC 061. HIV positive_HIV related diseases, accidental needle prick injury.pdf [6] Lecture slides: GC 102. Fever after chemotherapy infections in immunocompromised hosts [Handout].pdf (page 6) [7] Senior notes: Gen Clerk Anaes + Microbiology Summary.pdf (page 13)
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