Microbial Control and Sterilization – Key Concepts (Flashcards)

A set of practice flashcards covering sterilization, disinfection, antisepsis, and various microbial control methods and concepts discussed in the lecture notes.

What does sterilization mean?

Destruction of all microbial life.

What does disinfection mean?

Destruction or reduction of most microorganisms on inanimate objects.

What does antisepsis mean?

Reduction or elimination of microorganisms on living tissues.

What does decontamination refer to?

Removal of most microbes from both animate and inanimate surfaces; a generalized term, also called sanitization.

What is sanitization?

A form of decontamination that reduces microbial contamination to safe levels on surfaces.

Name the three broad categories of microbial control methods described in the notes.

Physical agents (heat and radiation), chemical agents (gas or liquid), and mechanical methods (filtration).

What is dry heat and give examples?

Dry heat uses hot air; examples include ovens and incineration.

What is moist heat and give examples?

Moist heat uses steam under pressure; autoclaves are a primary method (also boiling water).

What is pasteurization and its two methods?

Flash method: 71.6°C for 15 seconds; Batch method: 63–66°C for 30 minutes; inactivates viruses and most bacteria/fungi but not endospores.

What are ionizing vs non-ionizing radiation?

Non-ionizing radiation = UV light; Ionizing radiation = X-rays and gamma rays.

How does UV light kill microbes?

It forms thymine dimers in DNA, damaging genetic material and causing cell death.

How do chemical agents help control microbes?

Chemical agents can be gases (volatile antimicrobials) or liquids (sprays, soaps, hand sanitizers) used to kill or inhibit microbes.

What is filtration and what are HEPA filters?

Filtration is the mechanical removal of microbes; HEPA filters remove very small particles from air (used in ORs); water filtration depends on membrane size.

What is LifeStraw and what is it used for?

A portable water filtration device that removes microbes; used for safe drinking water while traveling.

What are endospores and why are they important in sterilization?

Endospores are the most resistant microbial forms; destroying them is a goal of sterilization.

What are prions and how are they described in the notes?

Protein-based infectious particles; described as having no protective structure and being highly resistant.

What is an antiseptic vs a disinfectant on living surfaces?

Antisepsis refers to disinfection on living tissues with agents that are safe for use on the body.

What is aseptic technique?

Practices to prevent the entry of infections into sterile tissues; essential in surgery, labs, and sterile procedures.

What do germicidal, bactericidal, fungicidal, tuberculocidal, and sporicidal mean?

Germicidal: kills germs; bactericidal: kills bacteria; fungicidal: kills fungi; tuberculocidal: kills Mycobacterium tuberculosis; sporicidal: kills spores.

What is the difference between bactericidal and bacteriostatic antibiotics?

Bactericidal antibiotics kill bacteria; bacteriostatic antibiotics inhibit bacterial growth.

What is thermal death time vs thermal death point?

Thermal death time is the shortest time required to kill the microbe; thermal death point is the lowest temperature needed to kill in ten minutes.

What is autoclave and what is it used for?

A device that uses pressurized steam to sterilize instruments, syringes, and some packaged foods.

What is autoclave tape and what does it indicate?

Indicator tape that changes color to show that a load has been autoclaved.