Investigation Steps
This is the very first conceptual step an epidemiologist takes when starting an investigation.
What is "prepare for field work"?
You want to compare the relative magnitude of two unrelated quantities, such as the number of apples to the number of oranges in a basket.
What is a ratio?
The "Father of Field Epidemiology" who used a spot map to identify a contaminated water pump during a London cholera outbreak.
Who is John Snow?
The pathogen type responsible for malaria.
What is protozoa?
An animal (like a mosquito, tick, or flea) that carries and transmits a germ but is not the cause of the disease.
What is a vector?
This step involves summarizing your data by Time, Place, and Person to look for patterns.
What is descriptive epidemiology?
You are calculating the probability or risk of illness during a corporate picnic by dividing the number of sick people who ate potato salad by the total number of people who ate it.
What is an attack rate (or incidence proportion)?
This scientist created germ theory and developed a set of "postulates" still used to prove a specific germ causes a specific disease.
Who is Robert Koch?
This pathogen is not a living cell and is composed of genetic material and a protein coat.
What is a virus?
An inanimate object (like a doorknob, towel, or toy) that can carry and spread an infectious agent.
What is a fomite?
This histogram displays the number of cases by time of onset and is the primary tool for tracking the course of an outbreak.
What is an epidemic curve (epi curve)?
You want to determine how many "lost years" a community experienced because several people died at a very young age compared to a baseline of age 65.
What is years of potential life lost (YPLL)?
A London haberdasher who was the first to quantify patterns of birth, death, and disease in 1662.
Who is John Graunt?
List 5 diseases caused by bacteria.
What are TB, strep throat, cholera, salmonella, lyme disease, whooping cough, tetanus, etc. (You can get points if you can prove your answer is correct)
The habitat in which an infectious agent normally lives, grows, and multiplies (can be humans, animals, or the environment).
What is a reservoir?
This step is the "primary goal" of any outbreak investigation.
What is "implement control and prevention measures"?
To find the strength of an association in a cohort study, you divide the risk of disease in the exposed group by the risk in the unexposed group.
What is the risk ratio (or relative risk)?
He proposed the "Causal Pies" model in 1976 to explain how different factors (component causes) work together to cause disease.
Who is Kenneth Rothman?
The type of pathogen that causes Cholera, a severe water diarrhea often linked to waterways and poor sanitation.
What is a bacterium?
A standard set of criteria used to decide whether an individual should be classified as having a specific health condition?
What is a case definition?
This "golden rule" states that a case definition must NEVER include this specific piece of information.
What is the hypothesized exposure?
In a case-control study where you don't know the total population size, you use the cross-product (ad/bc) to estimate risk.
What is the odds ratio?
He applied the modern concept of public health surveillance, which he called "continued watchfulness" over disease trends.
Who is Alexander Langmuir?
This pathogen type causes a highly contagious rash and fever called measles.
What is a virus?
The ability of an infectious agent to cause severe disease or death, measured by the proportion of cases that are fatal.
What is virulence?