Chapter 23- Control of Microorganisms

What are the requirements for killing endospores?

15psi at 121 for 15 minutes.

Antimicrobial agents that end in -static will?

Prevent the growth of a particular type of microorganism.

_______________________ are chemical disinfectants and antiseptics that damage cellular membranes and denature microbial proteins. They're capable of altering the surface tension of cell membranes causing their cellular contents to leak out.

Quaternary Ammonium Compounds (quats)

____ are widely used disinfectants that control microbial growth by denaturing proteins and by dissolving lipids in the cell membrane of microorganisms. most effective in aqueous solutions. intermediate level disinfectants.

alcohol

________ are a group of organic compounds that control microbial growth by reacting with the proteins in microorganisms and altering their chemical structure.

aldehydes

process by which microbial growth is inhibited on living tissue to prevent infection.

antisepsis

________ kill bacteria but not necessarily their spores

bactericides

used since ancient times to control microbial growth; water is ____ at 100C (212F); takes approx. 10 minutes to sterilize water without endospores.

boiling

Three methods of moist heat decontamination

boiling, free flowing steam, steam under pressure

form of incineration; temp around 1600 degrees F (871C)

cremation

destruction of pathogenic agents by chemical or physical means by applying the disinfectant to an inanimate object. it doesn't inactivate microbial endospores but kills most vegetative microorganisms.

disinfection

___________ kill insects

insecticides

__________ kill larvae

larvicides

refrigeration and freezing are used to preserve food by reducing ______ ______

microbial growth

________ is also known as carbolic acid

phenol

manual process by which microorganisms are removed from a surface; should be vigorous and forceful on inanimate objects, but human remains should be treated carefully.

scrubbing

______ are agents that kill bacterial and mold spores and can also be used during the process of terminal disinfection of embalming instruments and equipment.

sporicides

process of completely removing or destroying all life-forms, endospores, or their products on or in a substance; highest level of microbial growth control

sterilization

the lowest temperature at which all microorganisms are killed in 10 minutes

thermal death point

minimum time it takes to kill all microorganisms present

thermal death time

________ kill viruses

viricides

proteins are denatured more easily when they are ____

wet

What are the significant factors that influence the effectiveness of antimicrobial agents used to control microbial growth?

-nature of disinfectant -concentration of disinfectant -nature of material to be disinfected -number/type of microorganisms present -length of exposure to disinfectant -temp and pH of disinfectant during exposure -state of development of the cells

What can influence the effectiveness of a particular microbial agent?

-pH -viscosity -concentration of organic matter

What are the physical methods of controlling the growth of microorganisms?

-scrubbing -heat -cold -UV light

Household bleach contains what percent of sodium chlorite solution, which is several hundred times stronger than is needed to kill most disease causing microorganisms.

5%

most effective form of controlling microbial growth because pressure, temp, and length of exposure can be controlled. using an autoclave, water/liquid chemical is placed in it and items are placed on a tray inserted into the autoclave. Higher temps can be reached in a shorter time than boiling.

steam under pressure

form of nonionizing radiation that can effectively control the growth of microorganisms placed directly in its path. It inhibits microbial growth by damaging the cell's genetic material.

UV light

used most frequently in FH to treat hazardous waste; reduces the amount of waste to ashes; waste matter must remain in combustion chamber a sufficient time and at high enough temp to mix with available 02 to combust completely

incineration

________ is a compound of iodine and a surfactant like a detergent that can slowly release free iodine.

iodophore

Aromatic bases, known as pyrimidines, produced by the body to form nucleic acids (genetic material)

thymines

_____ is a solution of iodine and alcohol that is primarily used as an antiseptic.

tincture

the time in minutes it takes to kill 90% of the present microorganisms

decimal reduction time

What are the first two aspects of the embalming process?

disinfection and preservation

requires much more exposure time than moist heat; less effective because proteins don't denature as easily

dry heat

What are the three levels in controlling the growth of microorganisms?

sterilization, disinfection, antisepsis

What are the six halogens?

-hydrogen -astatine -fluorine -chlorine -bromine -iodine

________ is used to treat municipal drinking water and for maintenance of swimming pools. It is actually a gas, so it's often combined with water to form sodium hypochlorite.

Chlorine

When exposed directly to UV light, some microorganisms develop bonds between adjacent thymines in their ___

DNA

Why are halogens extremely caustic and aggressive?

They only require one electron to reach stability.

What can be used to sterilize embalming instruments when an autoclave is not available and is only active in an alkaline environment?

Glutaraldehyde

__________ are widely used disinfectants that work by oxidizing the components of microbial cells. Some also react with cellular proteins. They are the six elements found in the next to last column on the far right side of the periodic table.

Halogens

_______ controls microbial growth by oxidizing certain molecules within the microbial cell. Can be used in the form of a tincture or an iodophore.

Iodine

Antimicrobial agents that end in -cide will?

Kill a particular type of miroorganisms

Items placed in _______________ for 30 minutes on successive days. First day, items are introduced, which kills vegetative bacteria but not endospores. Materials incubated overnight to allow endospores to germinate. Second day, introduced again which kills new vegetative cells. Repeat once more.

free flowing steam

_________ kill both fungi and their spores

fungicides

________ Kill a variety of different types of microorganisms, but not necessarily their spores.

germicides