Principles of Disease and Epidemiology

pathology

the scientific study of disease

etiology

cause of the disease

pathogenesis

manner in which a disease develops

infection

invasion or colonization of the body by pathogenic microorganisms

disease

occurs when an infection results in any change from a state of health

normal microbiota

microbes that make up the body but do not cause any harm ranscient t

transient microbiota

may be present for several days, weeks, or months, then disappear

symbiosis

relationship between two organisms where one is dependent on another to survive

mutualism

type of symbiosis that benefits both organisms

parasitism

symbiosis where one organism benefits by deriving nutrients from the other

symptoms

gauge feeling of body discomfort

signs

objective changed the physician can observe and measures

syndrome

specific group of symptoms or signs may always accompany a particular disease

communicable disease

disease in which an infected person transmits an infection agent to another person who in turn becomes infected

contagious disease

diseases that are very communicable and capable of spreading very easily and rapidly incommunicable n

noncommunicable disease

disease that is not spread from host to another

incidence

number of people in a population who develop a disease during a specific time period

prevalence

number of people in a population who develop a disease during a specified time, regardless of when it first appeared

endemic disease

disease that is constantly present in a population

epidemic disease

disease where many people in a given area acquire it

acute disease

disease that develops rapidly but lasts only a short time

subacute disease

disease that is intermediate between acute and chronic

latent disease

disease where one of the causative agents remain inactive for a time but then becomes active to produce symptoms of the disease

primary infection

acute infection that causes the initial illness

secondary infection

caused by an opportunistic pathogen after the primary infection has weakened the body’s defenses

subclinical infection

inapparent infection; one that doesn’t show any noticeable illness

predisposing factor

makes the body more susceptible to a disease and may alter the course of the disease

incubation period

the interval between the initial infection and the first appearance of any signs and symptoms

prodromal period

short period that follows the period of incubation in some diseases

period of illness

disease is most severe during this period

period of decline

sign and symptoms sub-side during this time

period of convalescence

period where the person regains strength and and the body returns to its pre-diseased state

carriers

living reservoirs of infection

zoonose

diseases that occur in animals; can travel to humans

contact transmission

spread of disease by contact

direct contact disease

person-to-person

congenital transmission

mother - fetus

indirect contact transmission

nonliving object

droplet transmission

mucus droplets

waterborne transmission

contaminated water

food-borne transmission

incompletely cooked, poorly refrigerated, or unsanitary food

HAI’s

infectious disease patients acquire while being in treatment for other conditions

universal precautions

reduce the transmission of imirvobes in healthcare and and residential areas

standard precautions

basic practices to prevent transmission

transmission-based precautions

supplement standard precautions for individuals with known or suspected infections to prevent transmission

EID’s

diseases that are new or changing b

bioterrorism

use of pathogens or toxins to predict death

epidemiology

science that studies when and where disease occurs and how they are transmitted

descriptive epidemiology

entails all data that describe the occurrence of the disease s

experimental epidemiology

begins with a hypothesis about particular disease; experiments to test hypotheis are conducted

analytical epidemiology

analyses a particular disease to determine its probable cause