Download Disease Detectives 2014 Terms AGENT: A factor such as a

Disease Detectives 2014
Terms
AGENT: A factor such as a microorganism, virus or chemical substance whose
presence is essential for the occurrence of a disease.
CASE REPORT: a single report of a condition of interest, for example, one person with
an infection.
CASE SERIES: a report of multiple cases of the condition of interest, for example, many
people with an infection reported in certain time period and/or place.
CHAIN OF INFECTION: A process that begins when an agent leaves its reservoir
(habitat) or host through a portal of exit, and is conveyed (transferred) by some mode of
transmission, then enters through an appropriate portal of entry to infect a susceptible
host. Breaking any link in the chain can disrupt the epidemic.
(Organism Reservoir  Portal of Exit  Transmission  Portal of EntryVulnerable
Host  Organism)
CLUSTER: An aggregation (group) of cases of a disease or other health-related
condition, particularly cancer and birth defects, which are closely grouped in time and
place. The number of cases may or may not exceed the expected number; frequently
the expected number is not known.
CONTAMINATION: to be soiled, stained, or infected by contact or association <bacteria
contaminated the wound or food>
ENDEMIC: The constant presence of a disease or infectious agent within a given
geographic area or population group; may also refer to the usual prevalence of a given
disease within such area or group.
ENVIRONMENT: the physical and biological factors along with their chemical
interactions that affect an organism.
EPIDEMIC: The occurrence of more cases of disease than expected in a wide
geographical area or among a specific group of people over a particular period of time.
EPIDEMIOLOGY : a branch of medical science that deals with the incidence,
distribution, and control of disease in a population. It focuses on groups rather than
individuals. Epidemiologic data on diseases is used to find those at high risk, identify
causes and take preventive measures, and plan new health services.
EXPOSURE: having contact with the cause of or having a characteristic that causes a
particular health outcome (disease, injury, etc).
FOMITE: an inanimate object (as a dish, toy, book, doorknob, or clothing) that may be
contaminated with infectious organisms and serve in their transmission. For example, a
pacifier or toys used in a daycare center may transfer organisms between young
children.
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HOST: A person or other living organism that can be infected by an infectious agent
under natural conditions.
HYGIENE: conditions or practices (as of cleanliness) conducive to health
IMMUNITY: bodily power to resist an infectious disease that usually results from
vaccination or inoculation, a previous attack of the disease, or a natural resistance
INFECTION: Invasion of a host by pathogens, which may produce subsequent tissue
injury and progress to disease. A host can be infected and transmit the pathogen but not
get “sick”.
INFECTIOUS: capable of causing infection, a disease that can be transmitted from host
to host either directly or indirectly
OUTBREAK: (localized epidemic) – 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. A
sudden rise in the incidence of a disease <an outbreak of measles>
OUTCOME: something that follows as a result or consequence, <the outcome of an
investigation>
PANDEMIC: occurring over a wide geographic area and affecting an exceptionally high
proportion of the population <pandemic malaria>. An epidemic occurring over a very
wide area (several countries or continents) and usually affecting a large proportion of the
population.
PATHOGEN: a specific causative agent (as a bacterium, virus, prion etc.) of disease
PATHOGENIC: describes and agent that can cause or be capable of causing
disease
PATTERN: a set of characteristics that are displayed repeatedly
PUBLIC HEALTH: the art and science dealing with the protection and improvement of
community health by organized community effort and including preventive medicine and
sanitary and social science.
PUBLIC HEALTH SURVEILLANCE: the systematic, 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 toward controlling and preventing them.
RESERVOIR: the habitat in which an infectious agent normally lives, grows, and
multiplies, which can include humans, animals, or the environment
RISK: the probability that an event will occur or that an individual will be affected by, or
die from, an illness or injury within a stated time or age span.
SUSCEPTIBLE: having little resistance to the disease <persons susceptible to colds>
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SYMPTOM: a change in the body or mind which indicates that a disease is present
<a fever can be a symptom of a bacterial infection>
TREND: A long-term movement or change in frequency, usually upwards or downwards.
VECTOR: an animal intermediary in the indirect transmission of an agent that carries the
agent from a reservoir to a susceptible host. <An organism that transmits the infection as
a mosquito transmits the malaria protozoans>.
VEHICLE: An inanimate (nonliving) intermediary in the indirect transmission of an agent
that carries the agent from a reservoir to a susceptible host. <food can be a vehicle to
transmit bacteria to a host>
VIRULENT: highly infectious
4th and 5th GRADE ONLY
ATTACK RATE: frequency of morbidity, or speed of spread, in an at risk population. It is
used to project the number of victims to expect during an epidemic. The rate is arrived at
by taking the number of new cases in the population at risk and dividing by the number
of persons at risk in the population.
CASE-CONTROL STUDY: A type of observational analytic study. Enrollment into the
study is based on presence (``case'') or absence (``control'') of a disease or outcome.
Characteristics such as previous exposure are then compared between cases and
controls. This type of study starts with the outcome (disease, condition, injury, etc.) and
works backwards (retrospectively) to examine exposures to help identify the cause of
disease or an outcome.
Outcome  Exposure
COHORT: a group of subjects with a common defining characteristic (age, etc.) In
epidemiology, a countable instance in the population or study group of a particular
disease, health disorder, or condition under investigation. Sometimes, an individual with
the particular disease.
COHORT STUDY: an observational analytic study in which enrollment is based on
presence (“case”) or absence (“control) of an exposure. Cases and controls are
followed and the rates and risk for outcomes (disease, condition, injury, etc.) are
compared.
Exposure  Outcome
CONTROL GROUP: a population of those without the disease or exposure of interest to
compare to those who have the disease or exposure.
EPI CURVE: A histogram that shows the course of a disease outbreak or epidemic by
plotting the number of cases by time of onset.
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EXPOSURE: the condition of being subject to some detrimental effect or harmful
condition (i.e. infection).
GRAM STAIN: common technique used to differentiate two large groups of bacteria
based on their different cell wall constituents. The Gram stain procedure distinguishes
between Gram positive and Gram negative groups by coloring these cells red (negative)
or violet (positive).
INCIDENCE: rate of occurrence <a high incidence of illness> within a specified time
period; measures new disease (vs prevalence which measures all disease)
INCUBATION PERIOD: the period between the infection of an individual by a pathogen
and the manifestation of the disease it causes
INDEX CASE: the first documented case of a disease; Case 0
INFECTIVITY: The proportion of persons exposed to a causative agent who become
infected by an infectious disease
MORTALITY: the number of deaths in a given time or place: the ratio of deaths
occurring in a certain time in a given population to the number of individuals in the
population
ODDS RATIO: An odds ratio (OR) is a measure of association between an exposure
and an outcome. The OR represents the odds that an outcome will occur given a
particular exposure, compared to the odds of the outcome occurring in the absence of
that exposure. Odds ratios are most commonly used in case-control studies,
ONSET OF ILLNESS: the time when symptoms first present.
PREVALENCE: The number or proportion of cases or events or conditions in a given
population over a specified time period (vs. incidence which measures new disease).
PERIOD: a length or era of time. Used in epidemiology to define a amount of time that a
particular disease may be present in a population.
RELATIVE RISK: A comparison of the risk of some health-related event such as
disease or death in two groups
RESERVOIR: an organism in which a parasite that is pathogenic for some other species
lives and multiplies without damaging its host; also : a noneconomic organism within
which a pathogen of economic or medical importance flourishes without regard to its
pathogenicity for the reservoir <rats are reservoirs of plague>
VIRULENCE: The proportion of persons with clinical disease, who after becoming
infected, become severely ill or die.
ZOONOSIS: An infectious disease that is transmissible from animals to humans.
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