Module 10 pt 1 Flashcards
what is epidemiology
the study of the occurrence, distribution, and determinants of health and disease in a population
what is public health
the study of the population as a whole
what accounts for nearly half of all deaths in developing countries
infectious diseases
whats the major goal of epidemiology
identifying the nature of a disease and its transmission
mortality
the incidence of death in a population
morbidity
the state of being diseased (including fatal and non fatal disease)
DALY
measures disease burden in terms of lost years due to the disease
what is the incidence of a disease
number of new cases of the disease in a given period of time
what is prevalence of a disease
the total number of new and existing cases
what does sporadic mean
cases seen without geographical concentration
what are the patterns of incidence (3)
endemic
epidemic
pandemic
what is an endemic
disease that is constantly present in a population
what is an epidemic
a disease that occurs in a large number of people at the same time
what is a pandemic
epidemic that is widespread, usually worldwide
what is a reservoir
individuals who are infected with the pathogen that cause endemic diseases
what is herd immunity
defined as the resistance of a group to infection due to immunity of high proportion of the group
do immunized people protect nonimmunized people
yes
what is the basic reproductive number
R
what does the R number represent
the number of expected secondary cases of a given disease from each single case
what does a higher R number represent
a higher number of infections
when does a disease outbreak occur
when a number of cases of a disease are reported in a short period of time
what is the word for infections that show mild symptoms or no symptoms
subclinical infections
what are carriers
diseased individuals who show no symptoms or mild symptoms
what must a pathogen do to cause a disease
a pathogen must replicate and grow inside a host
whats a chronic infection
an infection where both the host and pathogen survives
what is an acute infection
pathogen can be a selective force - it can kill you
what are the 5 stages of disease
infection
incubation period
acute period
decline period
convalescent period
what is the infection period
organism invades and colonizes host
what is the incubation period
the time between infection and onset of symptoms
what is the acute period
the disease at its height
what is the decline period
disease symptoms are subsiding
what is the convalescent period
patient regains strength and returns to normal
what are the two types of epidemics
common source
host to host epidemic
whats a common source epidemic?
whats an example
epidemic that usually arises from contamination of water or food
cholera
whats a host to host epidemic?
what’s an example
the disease shows a slow, progressive rise and a gradual decline
chicken pox
what are the three ways that transmission occurs
point source
common source
person to person
what is a point source outbreak
people are exposed for a brief time to the same source so the number of cases rise rapidly to a peak and falls gradually
whats a continuous common source
when people are exposed to the same thing over a long period of time so the curve rises gradually
what is direct host to host transmission
when the individual transmits a disease directly to a susceptible host without an intermediate
what is indirect host to host transmission
transmission is facilitated by a living or nonliving agent (third party)
what Is a fomites
a non living third party (doorknob)
what is a vector
living third party (mosquito/tick)
can carriers be people in the incubation period of the disease
yes
can non living matter serve as a reservoir
yes (ex. soil)
what is zoonosis
any disease that primary affects animals but is occasionally transmitted to humans
