Quiz 2 FC Flashcards
The Iceberg Effect
-in healthcare we only see tip of iceberg, when people have a clinical disease with discernible effect
-the vast majority of people actually lie in subclinical disease without showing symptoms or visual change (below measurable level)
What are the 3 classes of a clinical infection?
Class A: Inapparent Infection Frequent
Class B: Clinical Disease Frequent; Few deaths
Class C: Infections usually fatal
Class A: Inapparent Infection Frequent
most people have the inactive dominant form (opportunistic infection: bacteria sits inside a prison until infected with something else or re-infected to trigger reaction) and are carriers
example: TB
Class B: Clinical Disease Frequent; Few deaths
majority of people show moderate symptoms and get disease but very few deaths
example: measles, monkeypox
Class C: Infections usually fatal
if you get it you die, very small amount are serious in symptoms and survive
example: rabies (oldest virus in humans)
What is Non-Clinical (Inapparent Disease)? There are 3 types
-Preclinical disease
-Subclinical disease
-Persistent (Chronic) disease
Preclincal disease
not apparent yet but it is destined to progress, don’t really know when you will get it yet (before manifestation, don’t have it, it manifests, you have it)
ex: Schizophrenia (mid 30s)
Subclincal disease
Disease that is not clinically apparent and it not likely to become clinically apparent, you might never manifest it- show no signs or symptoms and never know you have it
Persistent (Chronic) disease
person fails to “shake off” infection, and it persists for years at a time for life
ex: Diabetes
Carrier
Carry a genetic marker and can pass it on, but don’t express symptoms or have the disease
Explain how carrier status works in a family tree
You and your partner can both be carriers and have a child that is affected with the genetic marker and expressing the condition, is a carrier like you, or unaffected non-carrier
ex) sickle cell anemia, breast cancer (brecca 1/2)
Reservoir Host
The wildlife version of a carrier
-carriers pathogens without showing symptoms and then infects a human (or a tic) and human gets sick and shows symptoms
Case
an individual with the disease of interest
Incidence
the number of new cases during a given time
Incidence rate
the number of new cases of disease during a given time over the population at risk during a given time (often includes people who got the disease in the total)
INCIDENCE RATE= TOTAL NUMBER OF NEW INFECTIONS/NUMBER OF PEOPLE AT RISK
prevalence
the number of existing cases of a disease during a specific time period
ex: over the course of one year
prevalence rate
the number of existing cases of a disease existing a given time over the total population at risk during a given time to determine how quickly disease occurs in a population
P= TOTAL NUMBER OF CASES/TOTAL POPULATION
Endemic
-level of transmission can vary by location (country, state) but remains CONSTANT at a SPECIFIC LOCATION
-a disease that is always present in a particular population or region and is expected to remain indefinitely
*Health office will monitor case numbers if it becomes and epidemic due to a spike in baseline of level of transmission we expect
epidemic
The occurrence in a community or region of a group of illnesses of similar nature, clearly in excess of normal expectancy and derived from a common or a propagated source
-an endemic disease that has exceeded normal disease levels
-typically limited to one countries or a few (an increase in multiple regions or communities)
*Health organizations work to track and limit epidemics (WHO, CDC, Health Ministry)
spike
an increase from the baseline expected amount
secondary cases
cases that come after the primary case
disease outbreak
When a few, sick, non-immunized people spread a contagious disease to the population around which is healthy but not immunized
herd immunity
a few people are sick and non-immunized and spread contagious disease to surrounding community of a few non-immunized and healthy people who become infected, but the majority of the community is immunized and remains healthy because of that
ex: measles
incubation period
time elapsed between exposure to a pathogenic organism, a chemical, or radiation, and when symptoms and signs are first apparent
ex: Covid has a up to a 14 day incubation period
attack rate
the number of people at risk in whom a certain illness develops/ the total number of people at risk
secondary attack rate
The number of people exposed to the disease following exposure to the primary case (patient 0) who go on to develop the disease/ the total number of the population at risk
three questions when exploring the occurrence of a disease
Who was attacked by the disease?
When did the disease occur?
Where did the cases arise?
who (characteristics of human host)
Biological factors: sex, age, race
Behavioral risk factors: smoking, socioeconomic status, education
*measure data on say 1,000 ind and then find the group mean of say “age” to the whole population
When
certain diseases occur periodically
-seasonal due to temp variation
-influenced by weather, human migration, animal activity
*can predict the start and end of the flu season
Where
Disease is not randomly distributed in time or place
-influenced by multiple factors
-not limited to infectious disease
disease outbreaks def and which are most common?
sudden or abrupt increase in the number of cases of a disease
*new disease can also be defined as outbreaks
-typically limited to a specific location or community
in usa: foodborn illness
globally: neglected tropical disease
Steps of an Outbreak Investigation
1) establish the existence of an outbreak
2) verify the diagnosis
3) define a case and count cases
4) orient the data in terms of time, place, and person (group)
5) determine who is at risk for becoming ill
6) develop a hypothesis
7) compare hypothesis with established facts
8) plan a more systemic study
9) prepare a written report
10) execute control and prevention measures
EVery day Olga Decides Dumbly to Crush Pianos Passionately- Eeeeek!
Cross-Tabulation
tool used to determine which of the possible agents (infectious substance, person) is suspected to be the cause of the outbreak
-by comparing number of cases of people exposed to a certain variable
pandemic
-an epidemic that has expanded to a multinational or global level
ex: COVID-19, SARS
