Key Takeaways
- The chain of infection has six links: infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, and susceptible host
- Breaking any link in the chain prevents infection transmission
- Standard Precautions apply to all patients and include hand hygiene, PPE use, and safe injection practices
- Hand hygiene is the single most effective way to prevent the spread of infection
- Proper PPE sequence: put on (gown, mask, goggles, gloves); remove (gloves, goggles, gown, mask)
Last updated: January 2026
Infection Control Principles
Preventing infection transmission is a core nursing responsibility. The LPN/LVN must understand how infections spread and apply appropriate precautions consistently.
The Chain of Infection
Six links that must be present for infection to occur:
| Link | Definition | Examples |
|---|---|---|
| Infectious Agent | The pathogen | Bacteria, virus, fungus, parasite |
| Reservoir | Where the organism lives | Humans, animals, water, soil |
| Portal of Exit | How it leaves the reservoir | Respiratory secretions, blood, feces |
| Mode of Transmission | How it spreads | Contact, droplet, airborne, vector |
| Portal of Entry | How it enters new host | Broken skin, mucous membranes, respiratory tract |
| Susceptible Host | Person who can be infected | Immunocompromised, elderly, newborn |
Breaking the chain at ANY link prevents infection.
Modes of Transmission
| Mode | Description | Examples |
|---|---|---|
| Contact (direct) | Person-to-person touch | MRSA, scabies, herpes |
| Contact (indirect) | Contaminated object | Fomites, equipment |
| Droplet | Large respiratory particles (>5 microns) | Influenza, pertussis, COVID-19 |
| Airborne | Small particles (<5 microns), suspended in air | Tuberculosis, measles, varicella |
| Vector | Insect or animal carrier | Malaria, Lyme disease |
| Common vehicle | Contaminated food, water, medication | Hepatitis A, salmonella |
Standard Precautions
Standard Precautions apply to ALL patients, ALL the time.
| Component | Application |
|---|---|
| Hand hygiene | Before/after patient contact, after removing gloves |
| Gloves | Contact with blood, body fluids, mucous membranes |
| Gown | Contact with blood/body fluids likely |
| Mask/eye protection | Procedures with splash/spray risk |
| Safe injection practices | One needle/syringe per patient, single-use vials |
| Respiratory hygiene | Cover coughs, provide tissues |
| Sharps safety | No recapping, use safety devices |
Hand Hygiene
Hand hygiene is the #1 way to prevent infection spread.
When to Perform Hand Hygiene (WHO's "5 Moments"):
- Before touching a patient
- Before clean/aseptic procedures
- After body fluid exposure risk
- After touching a patient
- After touching patient surroundings
Hand Hygiene Methods:
| Method | When to Use | Duration |
|---|---|---|
| Alcohol-based rub | Hands not visibly soiled | 20-30 seconds |
| Soap and water | Visibly soiled, after C. diff exposure | 40-60 seconds |
Soap and water is required for:
- Visibly soiled hands
- After caring for patients with C. difficile
- After caring for patients with norovirus
- Before eating
- After using the restroom
Personal Protective Equipment (PPE)
Order of Application (Donning):
- Gown
- Mask/respirator
- Goggles/face shield
- Gloves (last)
Order of Removal (Doffing):
- Gloves (most contaminated)
- Goggles/face shield
- Gown
- Mask/respirator (last, outside room)
Hand hygiene after removing each piece and at the end.
Glove Use
| Do | Don't |
|---|---|
| Change between patients | Use same gloves for multiple tasks |
| Change after touching contaminated areas | Touch face or clean surfaces with contaminated gloves |
| Perform hand hygiene after removal | Assume gloves replace hand hygiene |
| Select appropriate size | Use damaged or expired gloves |
Respiratory Hygiene/Cough Etiquette
Teach patients and visitors:
- Cover mouth/nose when coughing or sneezing
- Use tissues, dispose properly
- Perform hand hygiene after
- Wear mask if coughing
- Maintain distance from others
Safe Injection Practices
| Practice | Rationale |
|---|---|
| One needle, one syringe, one patient | Prevents cross-contamination |
| Use single-dose vials when possible | Multi-dose vials can become contaminated |
| Never reenter vials with used needle | Introduces contamination |
| Perform hand hygiene before preparing | Prevents contamination |
| Use aseptic technique | Maintains sterility |
Cleaning and Disinfection
| Level | Purpose | Example |
|---|---|---|
| Cleaning | Remove visible soil | Soap and water |
| Disinfection | Kill pathogens on surfaces | Hospital-grade disinfectant |
| Sterilization | Kill all microorganisms | Autoclave, chemical sterilization |
Equipment categories:
| Category | Contact | Processing |
|---|---|---|
| Critical | Enters sterile tissue | Sterilization |
| Semi-critical | Contacts mucous membranes | High-level disinfection |
| Non-critical | Contacts intact skin | Low-level disinfection |
On the NCLEX-PN
Expect questions about:
- Standard precautions application
- Hand hygiene indications
- PPE donning and doffing sequence
- Breaking the chain of infection
Loading diagram...
Test Your Knowledge
After removing gloves, what should the LPN do NEXT?
A
B
C
D
Test Your Knowledge
When must soap and water be used instead of alcohol-based hand rub?
A
B
C
D