Transcript Terms in Epidemiology

Terms in Epidemiology
Ashry Gad Mohamed
Prof. of Epidemiology
What is Epidemiology?
Study of
distribution
and
determinants
of
health- related events
and application of this study to
control health problems.
Epidemic:
The occurrence of
more cases of disease than expected
In a given
area
or among
a specific group of people
over a particular time.
Endemic:
Constant presence
of a disease
or infectious agent
within a given
geographical area
or
population group
Pandemic:
An epidemic
occurring over
a very wide area
(several countries or contents)
and usually affecting a large proportion of
the population
Health:
A state of complete
physical,
mental,
social
and environmental
well being and not merely the absence of
disease or infirmity
Infection:
The
entry and development or multiplication
of an
infectious agents
in the
body
of person or animal
Contagious
Agent or disease
that is capable of being
transmitted
from one person to anther by contact or
close proximity.
Zoonosis
An infectious disease
that is
transmissible
under normal conditions from
animal to human.
Communicable disease
An illness due to a
specific infectious agent or its toxic
products
that arises through
transmission
of that agent from reservoir to susceptible
host.
Period of Communicability
The time
during which an
infectious agent may be transmitted
directly or indirectly from infected
person to anther person or animal.
Nosocomial infection
An infection
occurring in a
patient in healthcare facility
in whom it was
not present or incubating
at the time of
admission.
Reservoir
The habitat
in which infectious agent normally
lives, grows and multiplies.
It may be human, animal or environment.
Carrier
A person or animal
without apparent disease
Who
harbors a specific infectious agent
and is capable of transmitting the agent to
others.
Incubation period
The period from
infection
to the
Onset
of symptoms or signs of infectious disease.
Prepatent period
The period in people between
time of exposure
to parasite and the time when the parasite
can be
detected
in blood or stool.
Host:
A person or other living organism
That
can be infected
by an infectious agent under normal
condition.
Chemoprophylaxis
The administration of chemicals, including
antibiotics, to prevent the development of
an infection or the progression of an
infection to active disease or to eliminate
the carriage of a specific infectious agent
to prevent its transmission to disease.
Chemotherapy
The administration of
chemicals,
including antibiotics, to
treat diseases.
Morbidity
Any
departure,
subjective or objective
from state of physiological or psychological
well being.
Risk factor:
Factor
Associated
with an
increased occurrence
of disease or other health-related event or
condition.
Pathogenicity:
The proportion of persons
infected
after exposure to a causative agent, who
then
develops clinical disease.
Virulence
Degree of pathogenicity
of a microorganism as indicated by the
severity of the disease
produced and its ability to invade the
tissues of a host; the competence of any
infectious agent to produce pathologic
effects.
Thank you