Disease transmission concepts
the habitat (living or nonliving) in or on which an infectious agent lives, grows, multiplies, and on which it depends its survival in nature
What is a reservoir?
preventing a disease or disorder before it happens
What is primary prevention?
an epidemic affecting or attacking the population of an extensive region, country, or continent
What is a pandemic?
a person in a population who has been identified as having a particular disease, disorder, injury, or condition
What is a case?
the immediate transfer of an infectious agent from one person to another
What is direct transmission?
a nonliving intermediary such as a fomite, food, or water that conveys the infectious agent from its reservoir to a susceptible host
What is a vehicle?
any attempt to restore an afflicted person to a useful, productive, and satisfying lifestyle
What is rehabilitation?
ongoing, usual, or constant presence of a disease in a community or among a group of people
What is an endemic?
in an epidemic, this is the first disease case in the population
What is a primary case?
when droplets or dust particles carry the pathogen to the host and cause infection (e.g., respiratory viruses, pertussis, pneumococcal pneumonia, diphtheria, rubella)
What is airborne transmission?
an object such as a piece of clothing, a door handle, or a utensil that can harbor an infectious agent and is capable of being a means of transportation
What is a fomite?
aimed at the health screening and detection activities used to identify disease
What is secondary prevention?
there are two primary types of infectious-disease epidemics, this one arises from a specific source
What is a common-source epidemic?
this is when the first disease case is brought to the attention of the epidemiologists
What is an index case?
when an agent is transferred or carried by some intermediate item, organism, means, or process to a susceptible host, resulting in disease
What is indirect transmission?
an infectious organism in vertebrate animals (e.g., rabies virus, bacillus anthracis, Ebola virus, influenza virus) that can be transmitted to humans through direct contact
What is zoonosis?
this type of prevention does not require behavior change on the part of the individual (e.g., eating vitamin-enriched foods, drinking fluoridated water)
What is passive primary prevention?
there are two primary types of infectious-disease epidemics, this one arises from infections transmitted from one infected person to another
What is a propagated epidemic?
people who become infected and ill after a disease has been introduced into a population and who become infected from contact with the primary case
What is a secondary case?
when the anthropod (e.g., mosquito, flea, tick, lice) conveys the infection agent
What is vector-borne transmission?
an invertebrate animal (e.g., tick, mite, mosquito, bloodsucking fly) that transmits infection by conveying the infectious agent from one host to another
What is a vector?
to block the progression of a disability, condition, or disorder in order to keep it from advancing and requiring excessive care
What is tertiary prevention?
occurs when victims of a common-source epidemic have person-to-person contact with others and spread the disease, resulting in a propagated outbreak
What is a mixed epidemic?
an individual (or a group of individuals) who has all of the signs and symptoms of a disease or a condition yet has not been diagnosed as having the disease
What is a suspect case?
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?