[STUDY] Intro to Infection Prevention

Healthcare personnel (HCP)

• Paid/ unpaid person working in healthcare facility

Healthcare associated infections (HAIs)

• Infection acquired during delivery of healthcare

• Broad — could be hospital, care facility, ambulatory, dental office

Nosocomial infection

Infection specifically from hospital setting

What’s an infection?

Invasion of body tissues

Chain of infection requirements

1. Source or reservoir

2. Susceptible host with portal of entry

3. Mode of transmission

Source (reservoir)

Humans

• Mainly

• Patients, household members, visitors

• Symptomatic or Asymptommatic (incubation phase)

  • Acute infection or transiently/ chronically colonized

Contaminated objects

Susceptible host

• Depends on interaction between pathogen and host

• Depends on pathogen’s

  • Numbers

  • Pathogenicity

  • Virulence

  • Antigenicity

Pathogenicity

Ability to cause disease (yes or no)

Virulence

Severity of disease

Antigenicity

Ability to trigger immune response

Mode of transmission

Direct contact transmission

• Pathogen transferred without contaminated intermediate person, object, surface

  • No middle step

  • Person → person

• Blood/ OPIM enters mucous membranes or break in skin

Indirect contact transmission

• Pathogen transferred via contaminated intermediate person, object, surface

  • Person → middle step —> person

Respiratory transmission

• Transferred via breathing in respiratory droplets (greater than >5 (µm)

  • Large droplets — falls quick

• Within 3 ft of source

Airborne transmission

• Transferred via droplet nuclei

• Droplet nuclei are 1–5 µm

  • Small droplets — suspend in air

• Travels beyond 3 ft

What is standard precautions

• Caused by 1980 HIV pandemic

• Treat all blood, OPIM, bodily fluids, secretions with precaution

• Regardless if infection is suspected

OPIM

Other potentially infectious materials

• Body fluids

• Secretions / Excretions

• Non intact skin

• Mucous membrane

Standard precautions components (EI-EA)

Education

• Explain infection prevention policies — how prevent HAIs

Immunization

• Reduce risk of vaccine preventable HAIs

Engineering and work practice controls

• Eliminate hazard & promote safe behavior

• Respiratory/cough etiquette

• Hand hygiene

• PPE

• Sharp safety

• Clean/ sterile environment and devices

Administrative controls

• Understand medical conditions, post exposure, work restrictions

Transmission based precautions

Added ontop of standard precautions

• before disease is confirmed

• Remain in effect while patient is contageious, while pathogen is shedding, until illness resolves, until tests are negative

1. Contact precautions

2. Droplet precautions

3. Airborne precautions

Contact precautions

Prevent pathogen spread by

• Direct contact

• Contaminated objects

• Contaminated environmental surfaces

• 3 ft separation

• Must wear PPE + donning and doffing

Droplet precautions

Prevent pathogen spread by

• Respiratory droplets

• 3 ft separation

• Must wear mask

Airborne precautions

Prevent pathogen spread by

• Droplet nuclei (suspended)

3 levels of airborne precautions

1. Administrative control

• Identify patient

• Refer to facility — AIIR

• Ask about medical history (exposure, medical condition, signn/symptoms)

1. Environmental control

• Airborne infection isolate room (AIIR) — negative pressure from escaping

  • 6—12 ACH (air change per hr)

• Recirculate air through HEPA

1. Respiratory protection control

• Wear N95 respirator

Putative pathogens

• Suspected to cause disease but not proven

• Apply standard precautions and some transmission based precautions

Bloodborne pathogens (All standard precautions)

Hepatitis B virus (HBV)

• Inflammatory Liver disease

• Transmitted by blood, OPIM

• Prevention: Vaccine, standard precautions

Hepatitis C virus (HCV)

• Inflammatory liver disease

• Transmitted by infected blood (needles)

• Prevention: Standard precautions

Human Immunodeficiency virus (HIV)

• Cause AIDs

• Transmitted by bodily fluids, needles, blood

• Prevention: Standard precautions

Airborne pathogens (All standard precautions)

Measles virus

• Measles

• Transmitted by airborne or droplet nuclei

• Prevention: Standard precautions, vaccine, airborne

Varicella Zoster virus

• Chickenpox

• Transmitted by inhalation of aerosols

• Prevention: Standard, vaccine, airborne, contact (all)

Mycobacterium tuberculosis (TB)

• Tuberculosis

• Transmitted by: droplets & droplets nuclei

• Prevention: standard, airborne

SARS-CoV-2

• COVID—19

• Droplets, nuclei

• Standard, vaccine, airborne

Cross infection

• Patient → patient

• Patient → provider

• Provider → patient

Infection prevention protocol

• Dentist has responsibility

Infection prevent coordinator (IPC)

• Main protocol

• Explain policies

• Monitor effectiveness over time

Infecton control quality evaluation

1. Structure

• Availability of resources (materials, humans — staff, organization — post exposure follow ups)

1. Process

• Folowing standards (infection control)

1. Outcome

• Better knowledge, changed behavior, improve health

Infection control training / education

• Mandated every year

• Before HCP starting blood/ OPIM exposure

• Proof for 3 years