Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Disease Transmission
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Objectives
• Review disease transmission• Discuss standard precautions• Describe and demonstrate transmission-
based precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Modes of Disease Transmission
• Direct contact • Indirect contact• Droplet • Airborne
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Direct Contact Transmission
• Microbes directly transferred from an infected person to another person
• Examples– Contact with blood or other body fluids– Ungloved contact with a scabies-infested
patient– Ungloved contact with wounds or mucous
membranes
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Indirect Contact Transmission
• Microbes transferred through contaminated intermediate object
• Examples– Healthcare personnel not performing
adequate hand hygiene between patients– Sharing medical equipment without
cleaning or disinfection between patients– Defective medical equipment allowing for
inadequate disinfection or sterilization
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Droplet Transmission
• Respiratory droplets carrying infectious pathogens– Generated during coughing, sneezing,
talking, or certain medical procedures (e.g. suctioning)
– Droplets traditionally defined as > 5 µm– Typically refers to distances within 3 feet
of infected patient
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Airborne Transmission
• Dissemination of droplet nuclei containing infectious agents– Dispersed over long distances– Face-to-face contact not required– Special ventilation systems are required to
prevent airborne transmission
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Standard Precautions (1)
• Group of infection prevention practices that apply to ALL patients
• Based on principle that the following can contain transmissible infectious agents:– Blood and body fluids– Secretions – Excretions (except sweat)– Non-intact skin–Mucous membranes
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Standard Precautions (2)
• Applied during patient care based on nature of healthcare worker-patient interaction
• Dependent on anticipated blood, body fluid, or pathogen exposure
• Intended to protect both healthcare worker and patient
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Standard Precautions (3)
• Education and training are critical and include the following elements:– Hand hygiene– Respiratory hygiene/cough etiquette– Personal protective equipment (PPE)– Safe injection practices– Environmental considerations
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Transmission-Based Precautions
• Used when route of transmission is not completely interrupted using standard precautions alone
• Always used in addition to standard precautions
• Categories of precautions– Contact – Droplet – Airborne
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Contact Precaution Basics
• Intended to prevent spread of infectious agents transmitted by direct or indirect contact
• Applied when excessive wound drainage, fecal incontinence, or other body discharges increase the potential for environmental contamination
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Contact Precautions
• Single-patient rooms are preferred • For multi-patient rooms, > 3 feet separation
is recommended between beds• Healthcare personnel should wear gown and
gloves for ALL patient interactions• PPE donned upon entry and discarded
before exiting room
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Droplet Precaution Basics
• Intended to prevent spread of infectious agents transmitted by respiratory secretions or mucous membrane contact
• Droplets do not travel far and do not require special ventilation systems
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Droplet Precautions
• Single-patient rooms are preferred • For multi-patient rooms, > 3 feet separation
between beds and drawing the curtain is recommended
• Healthcare personnel should wear mask upon entering room
• Patients should wear mask (if tolerated) when transferred out of room– Follow respiratory hygiene/cough etiquette
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Airborne Precaution Basics
• Prevent transmission of infectious agents that remain infectious in air over long distances
• An airborne infection isolation room (AIIR) for placement of patient– Single-patient room– Special ventilation system
• Healthcare personnel should don a fit-tested N95 mask before entry
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Airborne Precautions
• Until AIIR can be instituted, the following should reduce likelihood of airborne transmission–Mask patient– Place patient in private room– Provide N95 or higher level respirator for
staff
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Reference:
Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings 2007 (CDC)
http://www.cdc.gov/hicpac/pdf/isolation/Isolation2007.pdf
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Example:
Key to abbreviations: see page 94
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Group Exercise (1)
• Use Appendix A for guidance• Each group has been assigned a disease • Please complete the table affiliated with your
disease• Type of precautions• Type of PPE• Room placement• Discontinuation of precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Group Exercise (2)
• Use completed table to set up patient’s room• Demonstrate how to set up PPE / hand
hygiene • Classroom discussion
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
NorovirusPrecautions
Personal protective equipmentRoom placement
Discontinuation of precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
NorovirusPrecautions Standard precautions; Contact
precautions for institutional outbreaksPersonal protective equipment
Contact precautions: gowns, gloves (masks)
Room placement
“cohort to separate airspaces and toilet facilities may help interrupt transmission during outbreaks”
Discontinuation of precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
InfluenzaPrecautions
Personal protective equipmentRoom placement
Discontinuation of precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
InfluenzaPrecautions droplet
Personal protective equipment
don mask upon entering room … patient to wear mask (if tolerated) when out of room
Room placement
Private or cohort with spatial separation of >=3 feet.
Discontinuation of precautions
5 days; duration of illness for immunocompromised patients
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Clostridium difficile (C. diff)Precautions
Personal protective equipmentRoom placement
Discontinuation of precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Clostridium difficile (C. diff)Precautions contact
Personal protective equipment
wear gown and gloves for ALL patient interactions; don PPE upon entry and discard before exiting room
Room placement
Private or cohort
Discontinuation of precautions
Duration of illness
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Streptococcus pneumoniae (single patient)
Precautions
Personal protective equipmentRoom placement
Discontinuation of precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Streptococcus pneumoniae (single patient)
Precautions standard
Personal protective equipment
Only for anticipated contact with secretions or excretions or blood or body fluids …
Room placement
Private room and cohorting are not necessary
Discontinuation of precautions
Standard precautions are NEVER discontinued
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Streptococcus pneumoniae (outbreak)
Precautions
Personal protective equipmentRoom placement
Discontinuation of precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Streptococcus pneumoniae (outbreak)
Precautions droplet
Personal protective equipment
don mask upon entering room … patient to wear mask (if tolerated) when out of room
Room placement
Private or cohort
Discontinuation of precautions
(while there is transmission in the facility)
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Pulmonary TuberculosisPrecautions
Personal protective equipmentRoom placement
Discontinuation of precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
Pulmonary TuberculosisPrecautions Airborne
Personal protective equipment
Fit-tested N95 mask
Room placement
Negative pressure room
Discontinuation of precautions
When patient is on effective therapy, is clinically improving and has 3 consecutive negative smears for TB
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
ScabiesPrecautions
Personal protective equipmentRoom placement
Discontinuation of precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
ScabiesPrecautions Contact precautions
Personal protective equipment
Gloves and gown.
Room placement
Private or cohort
Discontinuation of precautions
24 hours after completion of effective therapy
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
RSV(Respiratory Syncytial Virus)
Precautions
Personal protective equipmentRoom placement
Discontinuation of precautions
Office of Epidemiology and Prevention ServicesDIVISION OF INFECTIOUS DISEASE EPIDEMIOLOGYwww.dide.wv.gov
RSV(Respiratory Syncytial Virus)
Precautions Infants, children and immunocompromised adults: contact precautions
Personal protective equipment
For contact precautions, don gowns and gloves before entry; discard before leaving and practice hand hygiene
Room placement
Private or cohort
Discontinuation of precautions
Duration of illness