Etiology: The study of the cause of a disease
Pathogenesis: The development of disease
Infection: Colonization of the body by pathogens
Virulence - the ability to infect a host
Pathogenicity - the ability to cause disease in a host
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.
Epidemic – large numbers of people over a wide geographic area affected.
Cluster –an aggregation of cases over a particular period esp. cancer & birth defects closely grouped in time and space regardless of whether the number is more than the expected number. (often the expected number of cases is not known.) pandemic -An epidemic occurring over a very wide area (several countries or continents) and usually affecting a large proportion of the population. risk - The probability that an individual will be affected by, or die from, an illness or injury within a stated time or age span. vector - an animate 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. fomite - a physical object that serves to transmit an infectious agent from person to person.
A comb infested with one or more head lice would be a fomite or the dust particles containing infectious cold virus that remain after droplets of infected saliva are coughed into the air. zoonosis - An infectious disease that is transmissible from animals to humans. 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.
Scientific Method as related to Disease