INFECTION AND BACTERIAL INVASION Flashcards
- scientific study of disease
- concerned with the etiology and the manner in which a disease develops
- deals with structural and functional changes
pathology
invasion of microorganisms in the body
infection
changes in the state of health due to infection
disease
koch’s postulates
suspected causative agent must be absent from all ___ organisms but present in all ___ organisms
healthy, diseased
koch’s postulates
causative agent must be ___ from the disease organisms and grown in ___
isolated, pure culture
koch’s postulates
culutred agent must cause the ___ when inoculated into a healthy suscpetible organism
same disease
koch’ s postulates
the same causative agent must be isolated from the ___ disease organism
inoculated
diseases are classified based on the following
- behavior within a host
- sources of microorganisms
- disease occurence
- severity / duration of disease
- extent of host involvement
- host resistance
subjective changes in the body
symptoms
objective changes the physician can observe and measure
signs
specific signs of symptoms accompanying a disease
syndrome
number of new cases of a disease in a defined population during a specific time period
incidence
number of people in a population who developed the disease at a specified time, regardless of when it first appeared
prevalence
2 types of prevalence
period, point
number of cases of the disease existing in a population during a specific time period
period prevalence
number of cases of the disease existing in a population at a particular moment in time
point prevalence
types of disease based on behavior within a host
communicable, non-communicable, contagious
spreads from one host to another direct or indirectly
communicable
harmful functions that affect an individual
pathologic functions
- has symptoms
- apparent
case
does not from one host to another directly or indirectly
non-communicable
easily spreads from one host to another
contagious
types of disease based on source of microorganism
exogenous, endogenous, nosocomial
exposure to ___ causes the transmission of communicable disease
risk factors
disease came from the external environment
exogenous
disease came from inside our body
endogenous
disease came from the hospital
nosocomial
- no symptoms
- not apparent
incident
type of disease based on frequency of occurence
sporadic, endemic, epidemic, pandemic
occasional occurence of disease; seasonal; on and off
sporadic
- constant
- low level of population is affected
- all year round
- minimal cases
endemic
- relatively short
- gret number of affected population
epidemic
- at least three regions in the world
- worldwide occurence
pandemic
types of disease based on severity or duration
acute, chronic, subacute, latent
- develops rapidly
- only lasts for a short time
acute
intermediate duration of disease
subacute
- develops more slowly
- continual or recurrent for long periods
chronic
causative agent remians inactive for a time but then becomes active
latent
majority of the population be resistant against a disease; limits the transmission of miroorganism
herd immunity
type of infection based on extent of host involvement
localized, systemic, focal
infection limited to a small body area
localized infection
infection wherein microorganisms (or their products) are spread throughout the body
systemic infection
local infection enter blood or lymph vessel and spread to other specific parts of the body
focal infection
type of infection according to host resistance
primary, secondary, inapparent
acute infection that causes the intial illness
primary infection
infection caused by opportunistic microbe
secondary infection
infection that does not cause any noticeable illness
inapparent infection
enumerate the chain of infection
pathogen > reservior > portal of exit > mode of transmission > portal of entry > susceptible host
enumerate the steps of the development of disease
- incubation period
- prodromal period
- period of illness
- period of decline
- period of convalescence
time interval between the initial infection and the first apperance of any signs or symptoms
incubation period
a relatively short period characterized by early, mild symptoms of disease which are generally non-specific (e.g. fever, general aches, malaise)
prodromal period
presence of bacteria in the blood
bacteremia
the infection is already taking place in th blood
septicemia
toxins are present in the blood
toxemia
viruses are present in the blood
viremia
- period of maxial invasion
- manifestation of symptoms distinctive to the disease
period of illness
several outcomes of period of illness
- recovery
- fulminant infection
- acute to chronic form
- carrier state
- signs and symptoms start to subside
- person become more suscpetible to secondary infections (e.g. pneumodia after URTI)
period of decline
- person regains strength and return to pre-diseased state
- recovery occurs
period of convalescence
for a disease to perpetuate itself, there must be a continual source of the disase organism
reservoir
reservoir wherein disease may be directly or indirectly transmitted from one individual to another
human reservoir
living reserviors of infection
carriers
reservoir wherein disease may be caused by wild or domestic animals
animal reservoir
zoonotic infections may be transmitted through
- direct contact
- food and water contamintion
- consuming infected animal products
reservoir that includes insects and arachnids; VECTORS
arthropod reservoir
2 major nonliving reservoirs
soil and water
nonliving reservoir that harbors pathogens like clostridium botulinum and clostridium tetani
soil
nonliving reservoir tha has pathogens like vibrio cholerae and salmonella typhi
water (contaminated)
- person to person transmission
- touching, kissing, sexual intercourse
- common cold, infuenza, kissing disease
direct
- coughing and sneezing
- close proximity for droplets to be transmitted
droplet
- no direct human to human contacts
- transmitted through non-living objects
indirect
- through dust or aerosols
- < microns in size
- measles, TB, histoplasmosis
airborne
transmission of disease by a medium; inanimate
vehicle transmission
inanimate objects that can transmit disease
fomites
transmission by animate beings
vector transmission
type of vector transmission when pathogens is carried passively, by feet or other body parts of insects
mechanical transmission
type of vector transmission where active and more complex transmission
biological transmission
carrier with period of incubation
incubatory carrier
carrier with super delayed transmission
convalescent carrier
carrier that is actively transmitting disease
active carrier
carrier but asymptomatic (still infected)
healthy carrier
carrier but is not infected with the disease
passive carrier
diseases that are new and usually require transmission of microbes from animals to host
emerging infectious diseases (EID)
kissing disease
infectious mononucleosis
