Pathogenesis of Infectious Disease Flashcards
it is the ABILITY to cause disease
pathogenicity
it is a step or mechanism involved in the DEVELOPMENT of a diseas
pathogenesis
it is the study of the FACTORS that determine the FREQUENCY, DISTRIBUTION, and DETERMINANTS of the disease in populations
Epidemiology
it is observable phenomenon that can be identified by another person; Objective
sign
it is experience that cannot be identified by anyone; Subjective
symptoms
an organism that has capacity to cause disease affected by resistance to ANTIMICROBIAL and DISINFECTANT
virulence
T OR F: disease occurs if the bacteria or immunologic reactions to their presence cause sufficient harm to the person
T
process by which bacteria STICK to the surface of host cell
adherence
T OR F: after bacteria have entered the body, adherence is a minor initial step in the infection process
F (major)
T OR F: carrier is a person or animal with symptomatic infection that can be transmitted to another person or animal
F (asymptomatic)
multiplication of an infectious agent WITHIN the body
infection
the process whereby microbes ENTER host cells or tissues and SPREAD in the body
Invasion
microbial flora harbored by normal, healthy individuals
microbiota
a microorganism that does NOT cause disease
nonpathogen
an agent capable of causing disease only when the host resistance is IMPAIRED
opportunistic pathogen
a MICROORGANISM capable of causing disease
pathogen
the ability of a microorganism to produce TOXINS that contributes to the development of disease
toxigenicity
the quantitative ability of an agent to cause disease. it is may be used as reference to the SEVERITY of the infectious disease
virulence
T OR F: virulent agents cause disease when introduced into the host in big number
F (small)
virulence involved 4 characteristics
adherence, persistence, invasion, toxigenicity
what are the 6 characteristics of pathogenic bacteria
- transmissibility
- adherence to host cell
- persistence
- invasion of host cells and tissues
- toxigenicity
- ability to evade and survive the host immune system
when pathogens enter the body, there are two opposing forces, which are:
- the organism strive to_____the tissue and _______
- the body’s defense strive to _______ the invasion, ______ them, and _______ them off.
- invade, colonize.
- block, destroy, cast
the ability of pathogenic microbes to produce disease is tied up with complex clinical substance call _________
virulence factors
what are the attributes that enable pathogens to attach, escape destructions and cause disease
- capsule
- spores
- pili/ fimbriae
- enzymes
- toxins
T OR F: capsule has a anti-phagocytic function
T
the major mechanism by which pathogens cause disease are the _______ and ______ that they produce
- exoenzyme
- toxins
enzyme that degrades DNA
DNAse
enzyme that degrades keratin
keratinase
enzyme that breaks down the protein collagen which forms the connective tissue of muscles and other body organs
collagenase
enzyme that degrades hyaluronic acid, also known as the “spreading factor” since it helps in dispersing the pathogens to the tissues
hyaluronidase
bacterial enzyme that breaks down FIBRIN and dissolves CLOTS formed by the body.
bacterial kinases
enzyme that destroys the plasma membrane, especially around RBC
Lecithinase
enzyme that breaks down protein
protease
enzyme that cause damage to the host’s red blood cell and provides pathogens with a source of IRON
hemolysins
toxin that are produced INSIDE pathogenic bacteria, mostly common in GRAM-POSITIVE BACTERIA.
exotoxin
toxins that are part of the outer membrane of the cell wall of GRAM-NEGATIVE BACTERIA
endotoxin
the ______ are secreted or released into the surrounding medium following lysis
exotoxins
the _______ are liberated when the bacteria die and the cell wall breaks apart
endotoxins
where are exotoxins and endotoxins commonly found?
exotoxins = gram positive
endotoxins = gram negative
an exotoxins that interferes with normal nerve impulse
neurotoxin
exotoxin that affects the lining of the GIT
enterotoxin
exotoxins that kills the host cell or affect the function
cytotoxins
exotoxin that destroys neutrophils and macrophages
leukocidins
a specific group of symptoms and signs that always accompanies a specific disease _______
syndrome
a characteristic for a particular disease refer to signs and symptoms that point out the nature of a sickness, and can be useful in making a diagnosis
pathognomonic
invading pathogen are LIMITED to SMALL areas of the body
localized
- boils
pathogens SPREAD throughout the body through BLOOD or LYMPH
generalized or systemic
- measles
pathogens remain inactive for a time but become active to produce symptoms of the disease. example
latent
- tuberculosis
- syphilis
- hepa b
develops RAPIDLY but last only a short time. example
acute
- influenza
develops SLOWLY but body’s reaction may be less or severe
chronic
- TB, hepa B, AIDS
it is a manner that is transmissible from one human to another
communicable disease
it is not passed from person to person
non communicable disease
easily transmitted
contagious
occurs OCCASIONALLY within the population of a geographical area.
sporadic disease
T OR F: endemic disease is usually kept under control as a result of immunization and sanitary conditions
F (sporadic)
ALWAYS present within population of a particular geographical area
endemic disease
GREATER than usual number of cases of a disease in a particular region, usually occurring within a relatively SHORT period
epidemic disease (outbreak)
disease that is occurring in epidemic proportions in many countries SIMULTANEOUSLY
pandemic
what is the extent of infection is the pt is not experiencing any symptoms “asymptomatic disease”
subclinical infection
symptomatic disease
clinical infection
interval between the time of infection is received and the appearance of disease
incubation period
SHORT interval (prodrome); ill defined symptoms; characterized by the appearance of the first mild signs and symptoms
prodomal period
disease reaching its full development (acme); all signs and symptoms of a disease are apparent
period of illness
signs and symptoms subside
period of decline
RECOVERY stage; body returns to its predisposed state and health is restored
convalescent period
What is the chain of infection?
- There must be a _______.
- There must be a ______ of the pathogen ( a reservoir)
- There must be a portal of____
- There must be a mode of _____
- There must be a portal of _____
- There must be a _______
- pathogen
- source
- exit
- transmission
- entry
- susceptible host.
what are the possible portal of exit?
- ear (ear wax)
- broken skin (blood)
- skin (flakes)
- anus (feces)
- seminal vesicles (semen)
- urethra (urine)
- vaginal (secretions, blood)
- mammary glands (milk)
- mouth (saliva, sputum)
- nose
- eyes (tears)
what are the different portals of entry
- broken skin
- insect bite
- anus
- urethra
- vagina/ penis
- placenta
- mouth
- nose
- conjunctive of eye
- ear
T OR F: does the chain of infection needs to be broken at one point to stop the spread of infectious disease?
T
what are the different sources of infection (pathogens)
- bacteria
- virus
- fungi
- protozoans
what are the reservoirs of infection or sources where the pathogens can multiply?
- animals
- humans
- fomites
- vectors
Skin – penetration of ______
Respiratory Tract –________
Alimentary Tract - ________
Genitourinary Tract – ______
Placenta / Vertical Transmission
- intact skin
- inhalation
- food and drinks
- STD
what do you call a transmission DIRECTLY from host to host and it is not associated with infection of offspring during pregnancy
horizontal transmission
a transmission from one generation to the next through congenital infection
vertical transmission
