Disease Detectives - Vocab

Science Olympiad > Disease Detectives > Basic Vocab from Scioly

population oriented, studies community origins of health problems related to nutrition, environment, human behavior, and the psychological, social, and spiritual state of a population.

Classical Epidemiology

The study of the distribution and determinants of health related states/events in a population and how we can control the spread of diease

Epidemiology

studies patients in health care settings in order to improve the diagnosis and treatment of various diseases and the prognosis for patients already affected by a disease.

Clinical Epidemiology

heavily dependent on laboratory support

Infectious Disease Epidemiology

dependent on complex sampling and statistical methods.

Chronic Disease Epidemiology

studies how different environments may result in physical or neurological outcomes.

Environmental Epidemiology

studies unintentional and intentional injuries across a lifespan

Violence and Injury Epidemiology

application of the practice of epidemiology to produce outcomes or research efforts designed to address public health issues.

Applied Epidemiology

aims to describe distributions of diseases and determinants(person, place, and time).

Descriptive Epidemiology

measures the association between a particular exposure and a disease, using information collected from individuals, rather than from the aggregate population(hypothesis testing - study design).

Analytic Epidemiology

(1) Collect Data (2) Assessment (3) Hypothesis Testing (4) Action

Steps in Solving Health Problems

Methods used for collecting, compiling, and preserving health records

Informatics

Perform tests that confirm viruses and disease

Laboratories

showing no signs or symptoms, although can be the carrier of a disease

asymptomatic

an aggregation of cases over a particular period closely grouped in time and space, regardless of whether the number is more than the expected number.

cluster

reduction to zero of a disease in a defined geographical area due to deliberate efforts. This requires continued intervention measures.

elimination

present at a continuous level throughout a population/geographical area; constant presence of an agent/health condition within a given geographical area/population; refers to the usual prevalence of an agent/condition.

endemic disease

large number of people over a wide geographical area are affected.

epidemic

study of the cause of a disease

etiology

a physical object that serves to transmit an infectious agent from person to person.

fomite

an illness that is caused by medication or a physician.

iatrogenic

time in between when a person comes into contact with a pathogen and when they first show symptoms or signs of disease.

Incubation Period

first patient in an epidemiological study

index case(a.k.a. patient zero or primary case)

rate of disease in a population

morbidity

rate of death in a population

mortality

an infection that is acquired in a hospital.

nosocomial disease

more cases of a particular disease than expected in a given area or among a specialized group of people over a particular period of time.

outbreak

an epidemic occurring over several countries or continents and affecting a large proportion of the population.

pandemic

a serious, potentially life-threatening infectious disease that is usually transmitted to humans by the bites of rodent fleas.

plague

the probability that an individual will be affected by, or die from, an illness or injury within a stated time or age span.

risk

number of deaths due to a disease/number with the disease

Case Fatality Rate

number of deaths due to a disease/number in population

Cause-Specific Mortality Rate

the systematic and ongoing collection, analysis, interpretation, and dissemination of health data. The purpose of public health surveillance is to gain knowledge of the patterns of disease, injury, and other health problems in a community so that we can work towards their prevention and control.

surveillance

showing symptoms or signs of injury

symptomatic

an animal that transmits disease but is not the cause of the disease itself.

vector

an infectious disease that is transmissible from animals to humans.

zoonosis

number of new instances of disease in a population over a given time period. Expressed as X cases/Y population/Z time.

incidence

number of affected persons in the population at any given point in time. Expressed as X cases/Y population

prevalence

snapshot of the population and its rate of a certain disease at a point in time

point prevalence

tracks prevalence over a certain duration

period prevalence

diseases are reported by healthcare providers. This type, though simple and inexpensive, is often limited by incomplete reporting and quality variation in reporting.

passive surveillance

Health agencies contact health providers seeking reports. This ensures more complete reporting of conditions. Often used with specific epidemiological investigations or during an outbreak.

active surveillance

the syndrome of disease is monitored as a proxy for the disease. The syndrome must be infrequent and severe enough to warrant investigation of each identified case, and must be unique.

syndromic surveillance

professionals selected to represent a specific geographic area or group report health events to health agencies. This is used when high-quality data can't be obtained through passive surveillance. It involves monitoring trends or key health indicators and a limited network of reporting sites.

sentinel surveillance

humans are also capable of spreading disease following a period of illness, typically thinking themselves cured of the disease.

convalescent vectors

when an individual transmits pathogens immediately following infection but prior to developing symptoms

incubatory vectors

someone who can transmit a disease for a long period of time

chronic vector

has inherited a disease trait but shows no symptoms

genetic vector

someone who can transmit an infectious disease for a short amount of time

transient/temporary vector

person, place, and time

What is the first epidemiological triad?

An external agent, a vector or fomite that transmits the disease, and a susceptible host for the disease

What is the Chain of Transmission Triad?

to define the major points of a disease case

What is the Chain of Transmission Triad used for?

comparisons of geographical locations

ecological study

a survey, health questionnaire, “snapshot in time”

cross sectional study

compare people with and without disease to find common exposures

case-control studies

compare people with and without exposures to see what happens to each

cohort study

human experiment that randomly assigns participants to an experimental or control group

randomized controlled trial

research similarities with traditional experimental design or RCT, but lack element of random assignment to treatment/control; participants are assigned a group based on non-random criteria.

quasi experiments

most scientifically sound and best measure of exposure

advantages to trial study:

time consuming, unethical for harmful exposures, most expensive

disadvantages of trial study:

most accurate observational study, good measure of exposure, correct time sequence, good for rare exposures, easy risk calculation

advantages of cohort study:

time consuming, expensive, bad for rare diseases, possible loss of follow-up

disadvantages of cohort study:

can study rare diseases, relatively less expensive, relatively fast, good for rare diseases, good for long latency periods

advantages of case-control study:

possible time-order confusion, error in recalling exposure, only 1 outcome

disadvantages of case-control study:

fastest, least expensive, good for more than 1 outcome

advantages of cross-sectional study

possible time-order confusion, least confidence in findings

disadvantages of cross-sectional study:

a table which has two columns and rows for people with or without exposure and with or without disease; shows number of people with each characteristic

2×2 table

primary role is diagnosis and treatment of illness in individuals, preventive medicine(e.g., immunizations, smoking cessation, obesity counselling and other behavioral/lifestyle concerns) has only been addressed recently - focus remains on the individuals.

clinical approach

primary role is in control and prevention of disease in population or groups of individuals, some activities(e.g., diagnosing cases associated with outbreaks and treating persons with communicable diseases such as tuberculosis or syphilis) may overlap with those in clinical medicine.

public health approach

many microbes have a positive symbiotic relationship with other organisms

normal flora

both organisms benefit

mutualism

one organism and the other is not harmed or helped

commensalism

the condition(one organism is helped and the other is harmed) which takes place when humans are invaded by infectious microbes. A parasite-host relationship is created.

parasitism

chain of infection

1. agent

2. reservoir

3. portal of exit

4. mode of transmission

5. portal of entry

6. susceptible host

Koch’s Postulates

developed by German physician Robert Koch in the late 19th century to establish a causal relationship between a causative microbe and a disease

Evan’s Postulates

expanded on Koch’s postulates and addressed limitations in identifying causal relationships between diseases and infectious agents

point source epidemics

occurs when people are exposed to the same exposure over a limited period of time; curve rapidly rises and contains a definite peak followed by a gradual decline

exposure is prolonged over an extended period of time and may occur over more than one incubation period; down slope could be sharp or gradual

continuous common source epidemics

propoccurs when a case serves as a later source of infection; shape usually contains a series of successively larger peaks; as the outbreak progresses, the peaks flatten out

propagated (progressive source) epidemics

pertaining to how the participants are chosen or retained in a study; affects the accuracy and applicability of the data

selection biases

biases stemming from errors in accuracy or lack of completeness in data

performance biases

biases stemming from errors in accuracy or lack of completeness in data

measurement biases

biases stemming from errors in accuracy or lack of completeness in data

information biases

biases stemming from subjective judgement and irrational decision-making

cognitive biases

general errors affecting the entire study and framework

reporting biases

general errors affecting the entire study and framework

systemic biases

biases related to time in study design

temporal biases