8.1 Review of Infectious Disease Principles and Topics of Concern Flashcards
Carrier vs Host
Host - Person who provides living conditions to support a microorganism
Carrier - Person who carries an organism without apparent signs and symptoms and is able to transmit an infection to others
Colonization
- Microorganisms are present without host interference or interaction.
- Infection would include host interactions with the organism
- Disease is a person who has been infected and displays decline in wellness caused by the infection
Transient Flora
Recently acquired organisms that are likely to be shed in a relatively short period of time
Droplet Precautions
- Face mask is required but door may remain open
- Transmission is limited to close contact
How do Infections Occur
Source - Place where infectious agents live
Transmission - A way germs are moved into the susceptible person
Susceptible Person - A person at risk of obtaining the germs into the body
Most Common Healthcare Infection
- CDIFF
Source of Infection
- Dry surfaces in patient care areas (bed rails, medical equipment, countertops, tables)
- Indwelling medical devices (catheters and IV lines)
- Dust/Decaying Debris (Construction dust, wet materials from water leaks)
- Wet Surfaces or Moist Environments and Biofilms (Cooling towers, faucets, sinks, ventilators)
Biofilm
- Assemblage of surface bacteria that are enclosed in extracellular polymeric substance matrix which is irreversible associated (does not remove with gentle rinsing) with a surface.
- The enclosed material is primarily polysaccharide material
Healthcare Workers
- We are at risk population for infectious disease
Measels
- Highly contagious
- Can lead to pneumonia and encephalitis
Herpes Zoster
- Caused by re-activation of varicella-zoster virus (VZV) same virus that causes varicella (chickenpox). Shingles as well.
Vaccines
- Zoster vaccine live
- Recombinant Zoster Vaccine (RZV) - preferred vaccine for shingles
Infection
- In order for infection to occur a complete chain is necessary. This chain includes..
- Susceptible host
- Causative organism
- A reservoir of available organisms
- A portal of exit from the reservoir
- A mode of transmission from reservoir to host
- Mode of entry into susceptible host
Defintions
Infections agent
- Causative agent
Reservoir
- Place where microorganisms survive, multiply and wait for a host
- These require food, water, oxygen (anaerobic bacteria can live with little oxygen), proper temperature, pH, and light (most like darkness such as under dressings or body cavities)
Portal of Exit
- How they leave their reservoir to a new host (GI, GU, Respiratory, Skin, Mucous Membranes)
Mode of Transmission
- Direct, indirect, droplet, airborne, vehicles, vector
Portal of Entry
- How it enters another host
- GI, GU, Respiratory, Mucous Membranes
Susceptible Host
- Susceptibility to infection depends on the individuals immune system and resistance.
First Tier Standard Precautions
- All patients are colonized or infected with microorganisms
- Hand hygiene
- PPE
- Proper equipment handling and linen
- Environmental Control
- Prevention of injury from sharp devices and needles
- Avoidance of splash or spray of bodily fluids
- Patient placed in assigned rooms
Second Tier Transmission-Based Precautions
NEXT SLIDES
Airborne
- TB, Varicella
- Negative pressure room with doors closed
- N95 masks for hospital workers at all times when in the room
Droplet
- Influenza, Meningococcus
- Organisms transmit through close contact through respiratory secretions
- Face masks should be worn but the door may remain open as it only transmits through close contact
Herpes Zoster
- If patient is immunocompetent with herpes zoster then the following precautions should be used until the lesions are dry and crusted
- Standard
- Airborne
- Contact
- If the herpes is localized then just standard and contact precautions (lesions should be covered until dry and crusted.
Contact
- Organisms that spread skin-to-skin such as ARO (Antibiotic-Resistant Organisms) or C-Diff
- Barriers to prevent transmission
- These are easily transmitted between contact
- Masks are not needed
Pharmacoepidemiology
- Study of use and effects of drugs in well-defined populations (including drug use patterns and adverse drug effects)
- It is divided into acute and chronic epidemiology
CLABSI Prevention
BUNDLE APPROACH
- Hand hygiene
- Maximal barrier precaution
- Chlorhexidine skin antiseptics
- Optimal catheter site selection
- Daily review of line necessity with prompt removal of unnecessary lines
Community Acquired Infections Prevention
- Collaborate with CDC, state, local public health departments
Methods
- Sanitation techniques
- Regulated health practices
- Food preperation
- Immunization program
Vaccines
Two vaccines are licensed and recommended to prevent shingles in the US. Zoster vaccine live (ZVL, Zostavax) has been in use since 2006. Recombinant zoster vaccine (RZV, Shingrix), has been in use since 2017 and is recommended as the preferred shingles vaccine.
