Epidemiology Case Concepts
A person in a population who has been identified as having a particular disease, disorder, injury, or condition.
What is Case?
Contains, spreads, or harbors an infectious organism.
What is a Carrier?
An individual who has been exposed to and harbors a disease-causing organism (pathogen) and who has done so for some time, even though the person may have recovered from the disease.
What is an Active Carrier?
When droplets or dust particles carry the pathogen to the host and cause infection.
What is Airborne Transmission?
Preventing a disease or disorder before it happens, includes health promotion, health education, and health protection.
What is Primary Prevention?
First disease case in the population.
What is the Primary Case?
A nonliving intermediary such as clothing, food, or water that conveys the infectious agent from its reservoir to a susceptible host.
What is a Vehicle (fomite)?
An individual who has been exposed to and harbors a pathogen but has not become ill or shown any of the symptoms of the disease. Also called a passive carrier.
what is a Healthy Carrier?
When an arthropod (mosquito, flea, tick, lice) conveys the infectious agent. It does not cause the disease itself but is responsible for transmitting the pathogen to a host.
What is Vector-Borne Transmission?
Requires behavior change in the individual such as exercising and stop smoking.
What is Active Primary Prevention?
The first disease case brought to the attention of the epidemiologist.
What is the Index Case?
An invertebrate animal such as a tick or mosquito that transmits infection by conveying the infectious agent from one host to another.
What is a Vector?
An individual who harbors a pathogen and who, although in the recovery phase of the course of the disease, is still infectious.
What is a Convalescent Carrier?
An inanimate object that conveys an infectious agent to a host.
What is Vehicle-Borne Transmission?
Does not require behavior change on the part of the individual.
What is Passive Primary Prevention?
A person who becomes infected and ill after a disease has been introduced into a population and who is infected as a result of contact with the primary case.
What is Secondary Case
The habitat (living or nonliving in or on which an infectious agent lives, grows, and multiplies, and on which it depends for its survival in nature.
What is a Reservoir?
An individual who has been exposed to and harbors a pathogen is in the beginning stages of the disease, is displaying symptoms, and has the ability to transmit the disease
What is Incubatory Carrier
When the pathogen undergoes changes as part of its life cycle while within the host/vector and before being transmitted to the new host.
What is Biological Transmission?
Aimed at the health screening and detection activities used to identify disease.
What is Secondary Prevention?
An individual (or a group of individuals) who has all the signs and symptoms of a disease or condition but has not been diagnosed as having the disease or has the cause of the symptoms connected to a suspected pathogen.
What is Suspect Case?
An infectious organism in vertebrate animals that can be transmitted to humans through direct contact, a fomite, or a vector.
What is Zoonosis?
An individual who has been exposed to and harbors a pathogen and who can spread the disease in different places or at different intervals.
What is an Intermittent Carrier?
When a pathogen spreads using a host (e.g., fly, flea, louse, rat) as a mechanism for a ride for nourishment, or as part of a physical transfer process.
What is Mechanical Transmission?
Limiting any disability by providing rehabilitation when a disease, injury, or disorder has already occurred and caused damage.
What is Tertiary Prevention?