Microbiology and Risk Factors for Transmission

Question 1

What is the name of the model used to understand the infectious disease process?

Answer 1

The chain of infection (each link must be present in sequential order for infection to occur)

Question 2

Which factors influence the transmissibility of an organism and its ability to cause disease?

Answer 2

-Virulence
-Pathogenicity
-Infectivity
-Duration of exposure
-Size of inoculum
-Population immunity

Question 3

Define virulence

Answer 3

the ability to grow and multiply

Question 4

Define pathogenicity

Answer 4

the ability to cause disease

Question 5

define infectivity

Answer 5

the ability to enter tissues

Question 6

define size of inoculum

Answer 6

The number of organisms needed to cause disease

Question 7

List some examples of reservoirs

Answer 7

-Humans
-Animals
-Insects
-Food
-Environment (internal like inanimate objects and external like soil)

Question 8

List some portals of exit

Answer 8

-respiratory
-gastrointestinal
-skin/integumentary
-natural disaster (earthquake)
-inanimate objects
-weather (wind or rain)

Question 9

What is a portal of entry

Answer 9

Any opening from which an organism can enter

Question 10

List examples of portals of entry

Answer 10

-indwelling urinary catheters
-intravascular devices
-ventilators
-contaminated food or water
-coughing
-dressing changes

Question 11

List some anatomic/physiologic factors that render a host susceptible

Answer 11

-immunologic deficiencies
-trauma
-burns
-diabetes
-urinary retention
-age
-gender

Question 12

List some medical intervention factors that influence host susceptibility

Answer 12

-surgical/invasive procedures
-staffing ratios
-length of stay
-medication
-experience and education of healthcare providers
-appropriate device cleaning

Question 13

List some environmental factors that influence host susceptibility

Answer 13

-HH compliance
-barrier use
-contact with animals
-air handling systems
-plumbing
-population density

Question 14

What are some situations where airborne transmission is possible?

Answer 14

-a patient with an airborne disease is not immediately isolated
-employee does not use appropriate respiratory protection
-healthcare worker has airborne disease and comes to work
-visitor has an airborne disease
-ventilation is inadequate and carries the disease to other places
-ventilation system is contaminated with infectious agents

Question 15

List examples of direct contact

Answer 15

-contact occurs without appropriate barrier precautions
-PPE breaks
-HCP doesn’t recognize the need for PPE
-inadequate HH

Question 16

What is a primary risk reduction strategy

Answer 16

Focusing on prevention and providing outcome surveillance data

Question 17

What are 3 criteria used to cohort patietns?

Answer 17

1. common risk factors (infants born during the same time frame)
2. Common exposure to a communicable disease
3. Prevention of contact between patients infected/colonized with an organism or those newly admitted/not infected

Question 18

Define bioburden

Answer 18

the amount of bacteria present

Question 19

List some activities that reduce bioburden

Answer 19

-wash from clean to less clean areas
-preoperative showering using antimicrobial soap
-washing with antimicrobial soaps
-active surveillance for organisms common in a facility
-good oral hygiene
-good genital hygiene
-good HH
-treatment of remote site infections prior to surgery
-smoking cessation/weight loss

Question 20

what are some OHS policies that aid infection prevention

Answer 20

-immunizations
-restriction HCP working with communicable diseases
-assignment of patients to be cared for by HCP with immunity
-protocols for follow-up after employee exposure

Question 21

what are some visitor guidelines that minimize the likelihood of disease transmission

Answer 21

-identify areas of the facility where visiting is allowed
-post precautions visitors must take if visiting an area in isolation
-teach respiratory hygiene and cough etiquette
-provide warning signs for exclusion of visitors with respiratory diseases

Question 22

List patient factors that increase infection risk

Answer 22

-age
-poor nutrition status
-autoimmune
-malignant disorders
-diabetes
-burn wounds
-trauma
-human biome
-naive population status
-medical interventions (invasive devices)
-length of hospitalization
-exposure to antibiotics
-increased number of HCP examinations

Question 23

what are the 4 patient conditions that influence care requirements?

Answer 23

1. ability to ambulate
2. mental alterness
3. ability to perform ADLs
4. need for assistance to maintain normal body functions

Question 24

the Human Microbiome Project (HMP) indicated what?

Answer 24

That a patients normal body flora may increase their risk for normal infections