Exam 1 - Ch. 14 - Infection, Infectous Diseases, and Epidemiology Flashcards
Name two synonyms for normal microbiota.
Normal flora
Indigenous microbiota
Sites that are free of any microbes and are never colonized by normal flora.
axenic
How/when do people acquire most of their resident microbiota.
During birthing process and established during first months of life.
Normal microbiota that cause disease under certain circumstances.
Opportunistic pathogen
Site where pathogens live until they can infect a new host.
Reservoir of infection
What is the name for a disease naturally spread from animals to humans.
zoonoses
Animal reservoir for malaria.
monkey
Animal reservoir for toxoplasmosis.
cat
Animal reservoir for anthrax
cow
Animal reservoir for bubonic plague.
rat
Animal reservoir for Lyme disease.
deer
Animal reservoir for rabies.
bats
Animal reservoir for yellow fever.
monkey
Individuals that develop illness
case
Infected individual that are asymptomatic but infective to others.
carrier
Used to separate ill persons who have a communicable disease
isolation
Used to separate and restrict movement of well persons who may have been exposed to a communicable disease.
quarantine
How do soil, water, and food often become reservoirs of infection?
Presence of microorganisms often due to contamination by feces or urine.
The mere presence of microbes in or on the body
contamination
When organism evades body’s external defenses, multiplies, and becomes established in the body. MAY OR MAY NOT RESULT IN DISEASE.
infection
What are the 3 major portals of entry into the body (sites through which pathogens enter)?
Skin
Mucous membranes
placenta
What is the most common portal of entry?
Respiratory tract
A puncture wound or injection which deposits organisms directly into the tissues is not a true portal of entry, but a way to cheat or bypass the need for a portal of entry. What is this called?
Parenteral route
The ability of a substance to stimulate the production of antibodies or cell-mediated immune responses.
antigenicity
Results if the invading pathogen alters normal body functions (aka morbidity)
disease
The invasion of the host by a pathogen.
infection
Ability of a microorganism to cause disease.
pathogenicity
Degree of pathogenicity (how easily is it for the organism to cause disease).
virulence
Objective manifestations of disease observed or measured by others.
sign
Subjective characteristics of disease felt only by the patient.
symptom
Group of symptoms and signs that characterize a disease or abnormal condition.
syndrome
fever
sign
vomiting
sign
headache
symptom
swelling
sign
nausea
symptom
redness
sign
Organisms that colonize the body’s surfaces without normally causing disease.
Normal microbiota
Remain a part of normal microbiota of a person for life.
Resident microbiota
Remain in body for a few hours, days, months before disappearing.
Transient microbiota
5 areas that are axenic
alveoli of lungs CNS Circulatory system Upper urogenital regions uterus
Conditions that provide opportunities for opportunistic pathogens.
Introduction of normal microbiota into unusual site in body.
Immune suppression
Changes in the normal microbiota
What are three types of reservoirs?
Animal reservoirs
Human carriers
nonliving reservoirs
Which is usually considered a dead-end hosts?
humans
3 ways of acquiring zoonoses
Direct contact with animal or its waste
Eating animals
Bloodsucking arthropods
What 3 things are types of non-living reservoirs?
Soil, water, food.
Carcino-
cancer
col-, colo-
colon
dermato-
skin
-emia
Pertaining to the blood
Endo-
inside
-gen, gen-
give rise to
hepat-
liver
Idio-
unkown
-itis
Inflammation of a structure
-oma
Tumor or swelling
-osis
Condition of
-patho, patho-
abnormal
septi-
Literally, rotting; refers to presence of pathogens
terato-
defects
tox-
poison
What are the 3 components of the Triad/Triangle of health?
Agent
Host
environment
Which component of the Triad/Triangle of Health is microbiology focusing on?
agent
What is the name of the virulence factor that allows organisms to attach to a host and/or to each other to cause disease?
Adhesion factors
What is the name of the virulence factor that is secreted by pathogenic organisms to dissolve/break down tissues in the body?
Extracellular enzymes
What is the name of the virulence factor that harms tissues or triggers an immune response in the host and causes damage to the host?
toxins
What is the name of the virulence factor that allows pathogenic organisms to prevent phagocytosis by the host’s cells?
antiphagocytic factors
What are the 5 stages of infectious disease in order?
Incubation period Prodromal period Illness Decline Convalescence
Which stage of infectious disease is MOST severe?
Illness
How do pathogens usually leave the body?
Bodily secretions Blood Vaginal secretions Breast milk Bodily wastes
Pathogens leave the body though many of the same opening as the portals of entry. What do we call the openings when a pathogen is leaving?
Portals of exit
Period between infection and first symptoms
Incubation period
Short period of generalized, mild symptoms
Prodromal period
Signs/symptoms most evident
illness
Immune response/treatment vanquish pathogens, body slowly returns to normal
decline
Patient recovers from illness, tissues repaired and returned to normal
convalescence
When bacterial pathogens attach to each other they form what?
A biofilm
What extracellular enzymes are secreted by a pathogen to break down tissue and allow bacteria to penetrate deeper?
hyaluronidase and collagenase
Two types of toxins (virulence factors)
exotoxins and endotoxins
Example of an exotoxins.
cytotoxin, neurotoxin, enterotoxin
Examples of endotoxin
Lipid A
What are the 5 modes of transmission?
Contact transmission Vehicle transmission Vector transmission Airborne Perinatal
Inanimate object involved in indirect transmission.
Fomite
Animals that carry pathogens are called
Arthropod vectors
Only carry the pathogen.
Mechanical vectors
serve as host for pathogen.
Biological vectors
What two classes of arthropods have disease vectors?
Arachnids
insects
Type of arthropod with four pairs of legs. (ex: tick and mites)
arachnids
What are the most important arachnid vectors?
ticks
Are spiders a part of the arachnid vectors?
NO
Arthropods that have three pairs of legs and three body regions.
Insects: fleas, lice, flies, mosquitoes, kissing bugs
What are the most important insect vector?
mosquitoes
Which is most important and common of ALL vectors?
mosquitos
Number or NEW CASES of a disease in a given area during a given period of time.
incidence
Number of TOTAL CASES of a disease in a given area during a given period of time.
Prevalence
Incidence is associated with?
RISK
Prevalence is associated with?
Total + chronicity
Disease that normally occurs at regular intervals at a relatively stable incidence within a given population or geographical area.
Endemic
Only a few scattered cases within an area or population.
Sporadic
Occurs at a greater frequency than is usual for and area or population.
Epidemic
An epidemic that occurs simultaneously on more than on continent.
pandemic
Recent Ebola was a what?
pandemic
Careful tabulation of data concerning a disease (record location and time of the cases of disease and collect patient information)
Descriptive epidemiology
What is the first case of the disease called?
Index case
Infections acquired in health-care setting (patients or employees)
Nosocomial infections
Pathogen acquired from the HC environment.
exogenous
Pathogen arises from normal microbiota due to factors in the HC setting
Endogenous
Results from modern medical procedure.
latrogenic
What percentage of Americans acquire Nosocomial infections annually?
10%
What is the most effective way to reduce Nosocomial infections?
hand washing
Doctors, clinics, and hospitals send info to whom?
The local health department
The local health department sends info to whom?
State health department
The state health department sends info where?
CDC
State health department sends reports every ____ to the local health department.
month
The CDC sends reports every _____ to the state health department.
weekly
