EXAM 3 Flashcards
Inanimate items that may harbor microbes and aid in their transmission
Fomites
What is biological safety level one for laboratories
Microbes are not known to cause disease in healthy host and pose minimal risks to workers and the environment
What is Biological safety level 2
microbes are typically indigenous and are associated with diseases varying severity
they pose moderate risk to workers and the environment
What is Biological safety level 3
Microbes are indigenous or exotic and cause serious or potentially lethal diseased through respiratory transmission
What is Biological safety level 4
Microbes are dangerous and extoic posing a high risk of aerosol transmitted infections
which are frequently fatal w/o treatment or vaccines
uses antimicrobial chemicals safe enough for living tissues
antisepsis
complete removal or killing of all vegatative cells endospores and viruses
sterilizations
Clostridium botulinum are killed through ______ _____ protocals
commercial sterilization
the act of handwashing is an example of
degerming
wiping the skin with an alcohol wipe is another example of
degerming
the term _____ refers to the cleansing of fomites to remove enough microbes to achieve levels deemed safe for public health
sanitization
_____ is considered the most effective method of sterilization
autoclave
Those that inhibit microbial growth are indicated by the suffixes
stat or static
Autoclaves are _____ C or ins some cases _____ C
121
132
Autoclaves are typically at a pressure of ____ to ____ pounds per square inch (psi) for _____ min
15- 20 psi
20 min
_______ is used to kill pathogens and reduce the number of microbes that cause food spoilage
pasteurization
_____ slows microbial growth
Refrigeration
Laboratory and medical specimens may be frozen on dry ice or at ultra low temps ( ____ ) C for storage and transport
-70
including x rays and gamma radiation is an effective way to sterilize heat sensitive and packaged materials
ionizing radiation
like ultraviolet is unable to penetrate surfaces but is useful for surface disinfection
nonionizing radiation
_____ are stable long acting disinfectants that denature proteins and disrupt membranes
Phenolics (lysol)
____ are commonly used antiseptics that act by denaturing proteins and disrupting membranes
used at concentrations of 70%
Alcohols
_____ _____ is a gas sterilant that can penetrate heat sensitive packaged materials but it is also explosive and carcinogenic
Ethylene oxide
____ _____ are added to a variety of foods
chemical preservatives
_______ acid
_______ acid
________ acid
reduce intracellular pH
sorbic
benzoic
propionic
The discovery of the natural antibiotic by ______ _____ in _____
Alexander Fleming
1928
Alexander Fleming observed that penicillin inhibited _____ growth
staphylococcal
Antimicrobial drugs can be _______ or________ and these characteristics are important when selecting the appropriate drugs.
bacteriostatic (inhibit growth)
bactericidal (kill bacteria)
Life threatening infections such as acute ______ require the use of a bactericidal drug
Endocarditis
The use of ____ _____ antimicrobial drugs is preferred in many cases to avoid superinfection and the development of antimicrobial resistance.
narrow spectrum
B lactams includes
penicillins
cephalosporins
monobactams
carbapenems
B lactams are characterized by the presence of a b lactam _____ found within the central structure of the drug.
rings
because _____ _____ ___ are eukaryotic organisms like human cells, it is more challenging to develop antimicrobial drugs that specifically target them
fungi
protozoans
helminths
It is hard to target viruses because human viruses
replicate inside of human cells
HIV is typically treated with a combination of several antiretroviral drugs which may include _____ ______ ______ and drugs that interfere with viral binding and fusion to initiate infection
reverse transcriptase inhibitors
protease inhibitors
integrase inhibitors
Antimicrobial resistance is on the rise and is the result of
-selection of drug resistant strains
-overuse and misuse of antibacterials
-use of subtheraputic doses of antibacterial drugs
-poor patient compliance with drug therapies
common modes of antimicrobial drug resistance include
drug modification or inactivation
????
Our greatest concerns are _________ and cross resistance
multi-drug resistant microbes (MDR’s)
MDR’s are also known as
superbugs
Superbugs discussed have been dubbed the ESKAPE pathogens
Enterocccus faecium
Staphylococcus aureus
Klebsiella pneumoniae
Acinetobacter baumannii
Pseudomonas aerugionosa
Enterobacter spp
________ are useful for monitoring local trends in antimicrobial resistance susceptibility and for directing appropriate selection of empiric antibacterial therapy
Antibiograms
_____ of a disease are objective and measured
signs
______ are subjective and are reported by the patient
symptoms
_____ _____ are contracted in hospital setting,
nosocomial diseases
________ _______ are the direct result of a medical procedure
nosocomial diseases
______ due to genetics and environment
noninfectious
______ due to pathogens
infectious
some infectious diseases are ______ transmissible between individuals
communicable
other infectious diseases are _________ not spread from one person to another
noncommunicable
The periods of diseases include
Incubation period
Prodromal period
Period of illness
Period of decline
Period of convalescence
_______ period of disease occurs in an acute disease after the initial entry of the pathogen into the host
incubation
______ period of disease: the pathogen continues to multiply and the host begins to experience general signs and symptoms of illness
prodromal
period of _______: during which the signs and symptoms of disease are most obvious and severe
illness
period of _____ : during which the number of pathogen particles begins to decrease
decline
period of ______ : the patient generally returns to normal functions although some diseases may inflict permanent damage that the body cannot fully repair
convalescence
the ability of a microbial agent to cause disease is called _______
pathogenicity
the degree to which an organism is pathogenic is called
virulence
5 stages of pathogensis
Exposure
Adhesion
Invasion
Infection
Transmission
Pathogens can enter through a breach in the protective barrier of the skin and mucous membranes are said to enter by the ______ route
parenteral
Breaks in the skin such as
wounds
insect bites
animal bites
needle pricks
In pregnant women due to the placenta few pathogens are capable of crossing the
blood placental barrier
An example of a gram positive bacterium which causes foodborne disease is one example that poses a serious risk to the fetus is
Listeria Monocytogens
_____ classified as depending on the extent to which the pathogen spreads in the body
Infection
_______ confined to a small area of the body typically near the portal of entry
local
_____ a localized pathogen or the toxins it produces can spread to a secondary location
Focal
______ infection becomes disseminated throughout the body
systemic
______ leave through portals of exit
transmission
Bacterial toxins include
Endotoxin
Exotoxins
______ : a lipid A component of the LPS of the gram negative cell envelope
Endotoxin
______ : proteins secreted mainly by gram positive bacteria but also are secreted by some gram negative bacteria
Exotoxins
_______ trigger an excessive nonspecific stimulation of immune cells to secrete cytokines (chemical messengers)
Superantigens
The excessive production of cytokines often called a ______ ______
cytokine storm
Cytokine storms elicit a strong immune and inflammatory response that can cause life threatening
high fevers
low bp
multi organ failure
shock
death
_____ _____ bacterial pathogens may evade the host immune response by producing capsules to avoid phagocytosis
immune evasion
Capsules help to avoid phagocytosis surviving the intracellular environment of phagocytes degrading antibodies or through
antigenic variation
_____ _____ produces a waxy substance known as mycolic acid in its envelope
Mycobacterium tuberculosis
Influenza viruses use both _____ ____ and _____ _____ to avoid being recognized by the immune system
antigenic drift (minor changes)
antigenic shift (major changes)
_______ concerns the geographical distribution and timing of infectious disease occurrences and how they are transmitted and maintained in nature, with the goal of controlling outbreaks
epidemiology
______ : the study of the causes of disease and investigation of disease transmission
etiology
_____ is the number of new cases (morbidity or mortality) during a specified time period
incidence
____ is the total number of affected in the population again usually expressed as a proportion
prevalence
Patterns of incidence includ
Sporadic diseases
Endemic diseases
Epidemic diseases
Pandemic diseases
______ diseases only occur rarely and largely without geographic focus
sporadic
_____ diseases occur at a constant and often low level within a population
endemic
_____ diseases larger than expected number of cases occurs in a short time w in a geographic region
Epidemic
_____ diseases occur when an outbreak occurs on a world wide scale
pandemic
Types of epidemiology include
Descriptive
Retrospective
Prospective
Analytical
Experimental
____________ epidemiology: studies rely on case analysis and patient histories to gain information about outbreaks frequently while they are still occuring
Descriptive
_____ epidemiology: studies use historical data to identify associations w the disease state of present cases
Retrospective
_______ epidemiology: studies gather data and follow cases to find associations with future disease states
Prospective
________ epidemiology: studies are observational studies that are carefully designed to compare groups and uncover associations between environmental or genetic factors and disease
Analytical
______ epidemiology: studies generate strong evidence of causation in disease or treatment by manipulating subjects and comparing them with control subjects
Experimental
_______ transmission can be direct or indirect through physical contact with either an infected host or contact with a fomite that host has made contact with previously
Contact
____ transmission occurs when soil water or air carries an infectious agent to a new host
Vehicle
_______ transmission occurs when living organism carries an infectious agent on its body (mechanical) or as an infection host itself (biological) to a new host
Vector
