TEXTBOOK OF DIAGNOSTIC MICROBIOLOGY
COMPLETE PREPARATION GUIDE WITH
LABORATORY IDENTIFICATION AND CULTURE
TECHNIQUES REVIEW
◉ Sterilization.
Answer: the complete destruction or removal of all forms of
microbial life, including bacteria, viruses, fungi, and bacterial
endospores. Sterilization methods include autoclaving, dry heat, gas
sterilization, and filtration. Surgical instruments are sterilized before
use in operating rooms.
◉ Destruction.
Answer: the irreversible damage or killing of microorganisms so
they can no longer grow or reproduce. Destruction may occur
through heat, chemicals, radiation, or mechanical processes.
◉ Disinfectants.
Answer: chemical agents used on nonliving objects to destroy or
inhibit microorganisms. They are not safe for use on living tissue.
Examples include bleach, phenol, and glutaraldehyde.
◉ Antiseptic.
,Answer: a chemical agent applied to living tissue to reduce the
number of microorganisms and prevent infection. Antiseptics are
less toxic than disinfectants. Examples include iodine solutions and
chlorhexidine used before surgery.
◉ Biofilms.
Answer: structured communities of microorganisms enclosed in a
self-produced extracellular matrix and attached to surfaces. Biofilms
protect microbes from antibiotics and disinfectants. Dental plaque
and bacterial growth on catheters are examples of biofilms.
◉ Prions.
Answer: infectious protein particles that lack nucleic acids and cause
fatal neurodegenerative diseases by inducing abnormal folding of
normal proteins. Examples include Creutzfeldt-Jakob disease and
mad cow disease.
◉ Microbial load.
Answer: the number and types of microorganisms present on a
surface, object, or specimen before sterilization or disinfection. A
high microbial load requires more extensive decontamination.
◉ Sporicidal.
, Answer: capable of destroying bacterial endospores, which are
highly resistant forms of bacteria. Sporicidal agents include
hydrogen peroxide vapor and certain aldehydes.
◉ Moist heat.
Answer: a method of microbial control using hot water or steam to
denature proteins and destroy microorganisms. Autoclaving with
steam under pressure is the most effective moist heat sterilization
method.
◉ Pasteurization.
Answer: a moist heat process that reduces microbial numbers in
food and beverages to improve safety and shelf life without complete
sterilization. Milk is commonly pasteurized at specific temperatures
to destroy pathogens like Mycobacterium tuberculosis.
◉ Filtration.
Answer: a physical method of removing microorganisms from
liquids or air by passing them through a filter with microscopic
pores. HEPA filters remove airborne microbes in hospitals and
laboratories.
◉ Environmental Protection Agency (EPA).
COMPLETE PREPARATION GUIDE WITH
LABORATORY IDENTIFICATION AND CULTURE
TECHNIQUES REVIEW
◉ Sterilization.
Answer: the complete destruction or removal of all forms of
microbial life, including bacteria, viruses, fungi, and bacterial
endospores. Sterilization methods include autoclaving, dry heat, gas
sterilization, and filtration. Surgical instruments are sterilized before
use in operating rooms.
◉ Destruction.
Answer: the irreversible damage or killing of microorganisms so
they can no longer grow or reproduce. Destruction may occur
through heat, chemicals, radiation, or mechanical processes.
◉ Disinfectants.
Answer: chemical agents used on nonliving objects to destroy or
inhibit microorganisms. They are not safe for use on living tissue.
Examples include bleach, phenol, and glutaraldehyde.
◉ Antiseptic.
,Answer: a chemical agent applied to living tissue to reduce the
number of microorganisms and prevent infection. Antiseptics are
less toxic than disinfectants. Examples include iodine solutions and
chlorhexidine used before surgery.
◉ Biofilms.
Answer: structured communities of microorganisms enclosed in a
self-produced extracellular matrix and attached to surfaces. Biofilms
protect microbes from antibiotics and disinfectants. Dental plaque
and bacterial growth on catheters are examples of biofilms.
◉ Prions.
Answer: infectious protein particles that lack nucleic acids and cause
fatal neurodegenerative diseases by inducing abnormal folding of
normal proteins. Examples include Creutzfeldt-Jakob disease and
mad cow disease.
◉ Microbial load.
Answer: the number and types of microorganisms present on a
surface, object, or specimen before sterilization or disinfection. A
high microbial load requires more extensive decontamination.
◉ Sporicidal.
, Answer: capable of destroying bacterial endospores, which are
highly resistant forms of bacteria. Sporicidal agents include
hydrogen peroxide vapor and certain aldehydes.
◉ Moist heat.
Answer: a method of microbial control using hot water or steam to
denature proteins and destroy microorganisms. Autoclaving with
steam under pressure is the most effective moist heat sterilization
method.
◉ Pasteurization.
Answer: a moist heat process that reduces microbial numbers in
food and beverages to improve safety and shelf life without complete
sterilization. Milk is commonly pasteurized at specific temperatures
to destroy pathogens like Mycobacterium tuberculosis.
◉ Filtration.
Answer: a physical method of removing microorganisms from
liquids or air by passing them through a filter with microscopic
pores. HEPA filters remove airborne microbes in hospitals and
laboratories.
◉ Environmental Protection Agency (EPA).
