5.1 Infection Control & Standard Precautions
Key Takeaways
- Breaking any one link in the chain of infection (agent, reservoir, portal of exit, mode of transmission, portal of entry, susceptible host) stops the spread
- Hand hygiene is the single most effective measure to prevent healthcare-associated infection (CDC); use the WHO 5 Moments and 20-second technique
- CDC donning order is gown, then mask/respirator, then goggles, then gloves; doffing order is gloves, goggles, gown, mask
- Standard Precautions apply to EVERY resident at all times; transmission-based precautions (Contact, Droplet, Airborne) are added on top for specific pathogens
- Medical asepsis (clean technique) reduces pathogens; surgical asepsis (sterile technique) eliminates them — a CNA primarily practices medical asepsis
Infection control is one of the most heavily tested areas on the New Jersey CNA written exam, and hand hygiene is required in nearly every NNAAP skill you will demonstrate. Long-term care residents are often older, immunocompromised, or sharing close quarters, so a single lapse can cause an outbreak.
The Chain of Infection
An infection can only spread when six links connect. Break any one link and the infection stops.
| Link | Meaning | How a CNA Breaks It |
|---|---|---|
| Infectious agent | The germ (bacteria, virus, fungus) | Cleaning and disinfection |
| Reservoir | Where the germ lives (people, equipment, water) | Proper waste handling |
| Portal of exit | How it leaves (cough, blood, stool) | Cover coughs, contain fluids |
| Mode of transmission | How it travels (contact, droplet, air) | Hand hygiene, PPE |
| Portal of entry | How it enters (broken skin, mouth, catheter) | Clean technique, dressings |
| Susceptible host | A person who can get sick | Nutrition, vaccination, skin care |
Hand Hygiene — The #1 Measure
The Centers for Disease Control and Prevention (CDC) names hand hygiene the single most effective way to prevent healthcare-associated infections. Follow the World Health Organization (WHO) 5 Moments: before touching a resident, before a clean/aseptic task, after body-fluid exposure risk, after touching a resident, and after touching the resident's surroundings.
Wash with soap and water for at least 20 seconds when hands are visibly soiled or after caring for a resident with Clostridioides difficile (C. diff), because alcohol gel does not kill C. diff spores. Use friction, keep fingertips pointed down, and dry with a paper towel used to turn off the faucet.
PPE Donning and Doffing Order
Personal Protective Equipment (PPE) is worn in a strict CDC sequence so the dirtiest item is removed first.
| Step | Donning (Put On) | Doffing (Take Off) |
|---|---|---|
| 1 | Gown | Gloves |
| 2 | Mask or respirator | Goggles / face shield |
| 3 | Goggles / face shield | Gown |
| 4 | Gloves | Mask or respirator |
Perform hand hygiene before donning and after doffing. Gloves go on last and come off first because they are the most contaminated.
Standard vs. Transmission-Based Precautions
Standard Precautions treat all blood, body fluids, secretions, non-intact skin, and mucous membranes as potentially infectious for every resident, all the time. Transmission-based precautions are layered on top for known or suspected pathogens.
| Precaution | Examples | Key PPE / Action |
|---|---|---|
| Contact | MRSA, C. diff, scabies | Gown + gloves; dedicated equipment |
| Droplet | Influenza, pertussis, mumps | Surgical mask within ~6 feet |
| Airborne | Tuberculosis, measles, varicella | N95 respirator; negative-pressure room, door closed |
Residents in isolation still have rights: explain why precautions are used, visit often, and prevent loneliness.
Biohazard, Sharps, and Asepsis
Dispose of contaminated items in a red biohazard bag. Never recap or hand-pass needles; place sharps in a rigid, puncture-proof sharps container that you do not overfill. Medical asepsis (clean technique) reduces the number of pathogens and is what a CNA uses for routine care. Surgical asepsis (sterile technique) destroys all microorganisms and is used for invasive procedures — outside the CNA scope, but you may set up or assist.
A New Jersey nursing home resident is on Contact Precautions for Clostridioides difficile (C. diff). After helping the resident to the bathroom and removing your gloves and gown, what should you do for hand hygiene?
You are about to enter the room of a resident on Droplet Precautions for influenza to take vital signs. According to CDC sequence, in what order do you put on PPE?