Hospital Epidemiology and the Laboratory Flashcards
Lecture 3
Healthcare Associated Infections (HAIs)
infections acquired while receiving healthcare treatment
Colonization
presence of organisms on a body surface without disease
Infection
organisms invade body tissues causing disease
How do the US monitor HAIs?
Through the CDC’s National Healthcare Safety Network (NHSN)
What are NHSN reports used for?
to comply with state and federal reporting mandates, benchmark data
Common HAIs in Acute Care Settings
pneumonia, surgical site infection, gastrointestinal illness, UTIs, primary bloodstream infection
Leading HAI causing organisms in the US
C. difficle, S. aureus, Klebsiella spp., E. coli, Enterococcus spp. coagulase-negative Staphylococcus spp. and many more
What is THE most commonly identified pathogen causing HAIs?
Clostridium difficile (CDI)
Infection process
1) organism
2) reservoir
3) portal of exit
4) transmission
5) portal of entry
6) vulnerable hosts
* each link must be present for infection to occur
Why are hospitalized patients at high risk?
they have increased exposure to exogenous organisms form healthcare worker behavior like poor hand hygiene and contaminated shared equipment
When should you wash your hands as a healthcare worker?
1) before touching a patient
2) before clean/aseptic procedure
3) after body fluid exposure risk
4) after touching a patient
5) after touching patient surrondings
Standard Body Substance Precautions
with all patient contact, hand hygiene. Involves gloves, gown, mask, eye protection/face shield as needed
What are some diseases that can be transmitted by direct or indirect contact?
MRSA, VRE, CRE, C. difficile, norovirus, RSV
What are some diseases that can be transmitted by droplets and splashes?
Neisseria meningitidis, pertussis, group A strep, H. influenza, influenza, RSV, other respiratory viruses
What are some diseases that can be transmitted airborne?
tuberculosis, chicken pox, measles, influenza, SARS
What immunizations should health-care workers get?
Influenza, MMR, Varicella, Hepatitis B, and Pertussis
How can we prevent HAIs (vertically)?
active surveillance testing to identify carriers; contact precautions for patients with specific organism; decolonization of patients with specific organism
How can we prevent HAIs (horizontally)?
Standard precautions, environmental cleaning, antimicrobial stewardship, gloves and gowns, universal decolonization
Outbreak
more cases of disease than expected in a given area or amoung a specific group of people over a period of time
Endemic
predicted number of cases
Epidemic (outbreak)
significant increase from the endemic rate or an unusual infection
What are the goals of an outbreak investigation?
1) identify the agent, reservoir, and mode of transmission
2) eliminate the reservoir
3) prevent transmission
4) prevent future outbreaks
What are the steps to an outbreak investigation?
1) verify diagnosis
2) confirm outbreak
3) research the disease
4) case definition
5) descriptive epidemiology
6) develop a hypothesis
7) implement control and prevention measures
8) communicate findings
Pseudoepidemics
either false clusters of real infections or real clusters of false infections (typically due to error in diagnosis or testing)
