the primary cause of a health-related condition.
the ability of an infectious agent to cause immunity in the host.
the proportion of those exposed to the agent who develop the disease.
the idea that one event is the result of another event.
a systematic process used to study states of health and illness in an effort to control disease and promote health.
the study of the distribution of health and illness within the population and the factors that determine the population's health status.
the "process of enabling people to increase control over and to improve their own health" (World Health Organization, 1986, p. iii).
the client system affected by the particular condition under investigation.
a state of nonsusceptibility to a disease or condition.
the number of new cases of a particular condition within a specific population identified during a specified period of time.
the ability of an agent to invade the host system.
mode of transmission
the means by which the agent is transmitted from one host to another.
the ratio of the number of cases of a disease or condition to the number of people in a given population.
the ratio of the number of deaths in various categories to the number of people in a given population.
the ability of an agent to cause disease.
populations at risk
groups of people who have the greatest potential to develop a particular health problem because of the presence or absence of certain contributing factors.
portal of entry
the means by which the agent invades the host.
portal of exit
the avenue by which the agent leaves the host.
the total number of people in a given population affected by a particular condition at a specified point in time.
relative risk ratio
difference in the probability of developing a given condition between persons with specific risk factors for the condition and those without risk factors.
the ability of an infectious agent to survive in adverse conditions.
the probability that a given individual will develop a specific condition.
the ability to be affected by factors contributing to a particular health condition.
those individuals who would benefit from an intervention program and at whom the program is aimed.
the ability of an agent to produce toxins that are harmful to the human body.
the severity of the health problem caused by an agent.