Disinfection

This ppt contains all the information about the Disinfection. It is useful for students of the medical field learning Preventive and social medicine, Swasthavritta (Ayurved), and everyone who is interested in knowing about it

1. Dr. Shubhangi S. Kshirsagar
Assistant professor
Department of Swasthavritta & Yoga
15/3/2021

2. Definitions
Disinfectant–Usuallyachemicalagentwhich
destroysdiseasecausingpathogenorother
harmfulmicroorganism,butmightnotkill
bacterialspores.
Disinfection –
Thermalorchemicaldestructionof
pathogenandothertypeofmicro-organism.
Sterilization–freeofallformsofviable
organismincludingbacterialspores.
25/3/2021Dr. Shubhangi Kshirsagar

3. Antiseptic–Substancethatpreventsor
arrestsgrowthoforganismbyinhibiting
theiractivityorbydestroyingthem.
Asepsis-Preventionofcontactwith
micro-organism
Sterile-Stateofbeingfreefromallliving
micro-organisms.
35/3/2021Dr. Shubhangi Kshirsagar

4. Sanitizer–Agentthatreducesnumber
ofbacterialcontaminantstosafe
levelsasjudgedbypublichealth
requirement.
Germicide–Agentthatdestroysmicro-
organism especiallypathogenic
organism.
Deodorant–Asubstancewhich
suppressesorneutralizesbadodours.
Ex,Lime,bleachingpowder
45/3/2021Dr. Shubhangi Kshirsagar

5. Properties of an ideal disinfectant
1.Broadspectrum–wideantimicrobial
spectrum.
2.Economical–nohighcost.
3.Easytousewithclearlabeldirection.
4.Solubility–shouldbesolubleinwater.
5.Stability–stableinconcentrate&use
dilution.
6.Odourless–shouldhaveapleasantodour
7.Notaffectedbyenvironmentalfactors.
55/3/2021Dr. Shubhangi Kshirsagar

6. 8.Environmentallyfriendly–shouldnot
damagetheenvironment.
9.Cleaner–goodcleaningactivities.
10.Residualeffectontreatedsurfaceleavean
antibacterialfilmontreatedsurface.
11.Fastacting–rapidkill.
12.Surfacecompatibility–shouldnot
corrodeinstrument&metallicsurface.
13.Nontoxic–notharmfultotheuseror
patient.
65/3/2021Dr. Shubhangi Kshirsagar

7. Types of disinfection
1.Concurrent disinfection
2.Terminal disinfection
3.Pre-current (prophylactic)
disinfection
75/3/2021Dr. Shubhangi Kshirsagar

8. 1. Concurrent disinfection
Applicationofdisinfectivemeasuresassoon
aspossibleafterthedischargeof
infectiousmaterialfromthebodyofan
infectedperson,orafterthesoilingof
articleswithsuchinfectiousdischarges.
Itconsistsofusuallydisinfectionofurine,
faeces,vomit,contaminatedlinen,clothes,
hands,dressings,aprons,gloves,etc
throughoutthecourseofanillness.
85/3/2021Dr. Shubhangi Kshirsagar

9. 2. Terminal disinfection
Applicationofdisinfectivemeasuresafter
thepatienthasbeenremovedbydeathorto
ahospitalorhasceasedtobeasourceof
infectionorafterotherhospitalisolation
practiceshavebeendiscontinued.
Terminaldisinfectionisnowscarcely
practised.
Terminalcleaningisconsideredadequate,
alongwithlongwithairingandsunningof
rooms, furniture and bedding.
95/3/2021Dr. Shubhangi Kshirsagar

10. 3. Precurrent(prophylactic) disinfection
Ex.
Disinfection of water by chlorine
Pasteurization of milk
Hand washing
105/3/2021Dr. Shubhangi Kshirsagar

11. Classification of Disinfectiveagents
Disinfection
Natural
agent
1. Sunlight
2. Air
Physical
agent
1. Burning
2. Hot air
3. Boiling
4. Autoclave
5. Radiation
Chemical
agent
SolidLiquidGases
115/3/2021Dr. Shubhangi Kshirsagar

12. Chemical agents
Chemical agents
Solid
1. Lime
2. Bleaching powder
3. Pot Permangate
Liquid
1. Phenol & their
compound
2. Quaternary ammonia
compound
3. Halogen compound
4. Oxidizing agent
5. Heavy metals
6. Alcohol
7. Formalin
Gases
1. Formalin
2. Chlorine
3. Ethyline
oxide
125/3/2021Dr. Shubhangi Kshirsagar

13. Natural agents
135/3/2021Dr. Shubhangi Kshirsagar

14. 1. Natural agents
1.Sunlight
Directandcontinuousexposuretosunlightis
destructivetomanydiseaseproducing
organism.
UVraysarelethaltobacteriaandsome
viruses.
Ex.Linen,beddings,furnituredisinfectedby
exposuretosunlightforseveralhours.
Salmonellatyphidestroywithin30min.
Mycobacteriumtuberculidestroywithin3-
4hr.
145/3/2021Dr. Shubhangi Kshirsagar

15. 2. Air
Exposuretoopenair(airing)actsbydryingor
evaporationofmoisture,whichislethalto
mostbacteria.
155/3/2021Dr. Shubhangi Kshirsagar

16. Physical agents
165/3/2021Dr. Shubhangi Kshirsagar

17. 2. Physical Agent
1. Burning/incineration
Excellentmethodofdisinfection
Usedfordisinfectionof
Inexpensivearticles
Ex.Dressings,swabs,rags
Additionofsawdust,paper,
keroseneorothercombustible
materialaidinburning.
Faecescanbedisposedoffby
burning
175/3/2021Dr. Shubhangi Kshirsagar

18. 2. Hot air
Usedfordisinfectionglassware,syringes,swabs,
dressings,oil,sharpinstrument.
Doneinhotairoven
Temperatureofairinovenshouldbe
maintainedat160-180
0
Cforatleast1hourto
killspore.
Drawback–notsuitablefordisinfectionof
bulkyarticles(mattresses),becauseithasno
penetratingpower.
185/3/2021Dr. Shubhangi Kshirsagar

19. Hot air oven
195/3/2021Dr. Shubhangi Kshirsagar

20. 3. Boiling
Effective method
Boiling for 5-10min will kill bacteria, but not
spores & viruses.
Boiler provide temp well above 90
0
C (for spore
destruction temp needs >100
0
C
Ex. Linen, rubber goods (gloves), small instrument
which are not used for subcutaneous insertion.
Additionof1%soap&0.3%ofwashingsodato
enhancetheeffectofboiling.
Boilingfor30minisadequatefortodisinfect
linen,utensils&bedpan.
205/3/2021Dr. Shubhangi Kshirsagar

21. Drawbacksofboiling–
1.Slowprocess
2.Unsuitableforthickbeddings&woolen
materialastheyshrinkanditfixes
albuminousstain.
215/3/2021Dr. Shubhangi Kshirsagar

22. 4. Autoclaving
Autoclavearesterilizerswhichoperateathigh
temp(>100
0
C)&pressure.
Theygeneratesteamunderpressure(saturated
steam),whichismosteffectivesterilizingagent.
Itworksonprincipleofdomesticcooker.
Itattainstempof122
0
Cunder15
lbs/sq.inch(1kg/sq.cm)pressure
Itactsbygiving–latentheat.
225/3/2021Dr. Shubhangi Kshirsagar

23. MosteffectiveforsterilizationofLinen,
dressings,gloves,syringes,certaininstruments
andculturemedia.
Notsuitableforplastics&sharpinstruments.
Categories–
a.Gravitydisplacementautoclaves
b.Highspeedprevaccumesterilizer
235/3/2021Dr. Shubhangi Kshirsagar

24. 5. Radiation
Ionizingradiationareusedforsterilizationof
bandages,dressings,catgut&surgicalinstruments.
Theobjectstobesterilizedareplacedinplasticbags
beforeradiationandtheywillremainsterileuntil
opened.
Ithasgreatpenetratingpowerwithlittleorno
heatingeffect.
Mosteffectivemethod,butverycostly
Commercialmethodsofsterilizationarenormally
carriedoutbygammaradiation(atomic).
Thistechniquerequiresspecialpacking&
equipment.
245/3/2021Dr. Shubhangi Kshirsagar

25. Chemical agents
255/3/2021Dr. Shubhangi Kshirsagar

26. 1. Phenol & related compound
1.Pure phenol /
carbolic acid
Not effective
disinfectant
2. Crude phenol (Phenol+Cresol)
Dark oily liquid
Effective against gram +ve& -ve
bacteria.
Slowly effective against spores,
acid fast bacilli & certain viruses.
5% strength used mopping
floors & cleaning drains.
Should not used in less than
10% strength for disinfection of
faeces.
Aqueous solution 0.2 -1% -
bacteriostatic.
265/3/2021Dr. Shubhangi Kshirsagar

27. Phenol & related compound
3. Cresol
Excellent coal tar
disinfectant.
3-10times effective
than phenol.
5-10% soln-faeces&
urine disinfection.
All purpose general
disinfectant.
4. Cresol emulsion
Cresol emulsified
with soap
Lysol, Izal, cylline
Lysol –50-60%
cresol powerful
disinfectant
2% lysol-feces
disinfection
275/3/2021Dr. Shubhangi Kshirsagar

28. Phenol & related compound
5. Chlorhexidine
(Hibitane)
Skin antiseptic
Highly active against
vegetative gram +ve
organism.
Moderately active
against-gram +ve
microbes.
1% lotion/cream –
burn & hand
disinfection.
6. Hexachlorphane
Antiseptic
Highly Active
against gram +ve
organism.
Less active against
gram –ve
organism.
285/3/2021Dr. Shubhangi Kshirsagar

29. Phenol & related compound
7. Dettol(Chloroxylenol)
Non toxic antiseptic and can be used safely
in high concentration.
Active against streptococci.
5% solnused for disinfection of instrument
and plastic equipment. (15 min).
295/3/2021Dr. Shubhangi Kshirsagar

30. 2. Quaternary Ammonia compound
1. Cetrimide/Cetavlon
Bactericidal against
vegetative gram +ve
organism
Less on –veorganism
Used in 1-2% strength
Soluble in water
2. Savlon
(Cetavlon+ Hibitane)
1:6 (Savlon: Spirit)-more
effective than 1:20 aq
Soln.
Use -
Plastic appliences
disinfection (normal
strength) within 20min
Thermameter-
3min(1in 6)
Lippesloop
305/3/2021Dr. Shubhangi Kshirsagar

31. 3. Halogen & their compound
a. Chlorine & chlorine compound
Bactericidal
Fungicidal
Virucidal
Tuberculocidal
Sporicidal
b. Iodine
315/3/2021Dr. Shubhangi Kshirsagar

32. a. Chlorine & chlorine compound
1. Bleaching powder/ Chlorinated lime
Formula –CaOCl
2
White amorphous
powder
Pungent smell of
chlorine
33% chlorine
Drawback –
Unstable compound.
Loses its chlorine
content on storage.
Action rapid, but brief.
Uses -
Disinfection of feces &
urine in 1hr (5% soln)
Disinfection of well (Water)
Deodorant
325/3/2021Dr. Shubhangi Kshirsagar

33. 2. Hypochlorite
Solid (Ca hypochorite) and
liquid (Na hypochlorite)
Sodium hypochlorite-
household bleach
Broad spectrum of
Antimicrobial activity
3. Chlorine tablets/
halozenetablets
Water
disinfection
(small quantity)
335/3/2021Dr. Shubhangi Kshirsagar

34. b. Iodine solution / tinctures
1.Iodine
solution/tincture
Antiseptic on skin
Cheap, readily
available, quick action
Bactericidal
Fungicidal
Virucidal
Lethal to spore
bearing organism
2. Iodophores
Combination of Iodine
& stabilizing agent
Ex. Povidoneiodine
(betadine)
Non irritant
Use –blood culture
bottles & medical
equipment disinfection
345/3/2021Dr. Shubhangi Kshirsagar

35. 4. Oxidizing agent
1. KMnO4
Purple black crystalline powder
Uses –
Aquarium disinfection.
Swimming pool disinfection.
Fruits & vegetable
disinfection.
2. Hydrogen peroxide -
H
2O
2
Bactericidal
Fungicidal
Virucidal
Sporicidal
Uses -
Hospital –surface disinfection
3% soln–Antiseptic, Cleaning
wounds
3. Paraaceticacid (H
2O
2+acetic acid)
Active against gram +ve, fungi, yeast within 5min at<100ppm
In presence of organic matter 200-250ppm is required.
For Viruses –12-2250ppm 355/3/2021Dr. Shubhangi Kshirsagar

36. 5. Alcohol
Ethyl&isopropylalcohol–antiseptic&disinfectant.
EthylalcoholintheformIndustrialmethylatedspirit
–commonlyuseforskindisinfection.
Purealcohol–notdisinfectant,butwhendiluted
withwater60-90%volume;itactsasbactericidal,
fungicidal,virucidal,tuberculocidal;butdoesnot
destroybacterialspore.
365/3/2021Dr. Shubhangi Kshirsagar

37. 6. Formaldehyde
1. Formaldehyadesoln
(formalin)-
Effective against
vegetative bacteria, fungi
and many viruses.
Slowly effective against
bacterial spores (eg.
tetanus spore) and acid
fast bascilli.
Use –2-3% soln(formalin
40%) for spraying room,
walls, furniture.
b. Formaldehyade
gas
Most commonly used
for disinfection of
rooms
books, bed, blanket
and other which can’t
boil
Operation theater
disinfection
375/3/2021Dr. Shubhangi Kshirsagar

38. 7. Lime
Cheapest
Used in the form of fresh quick lime or 10-20%
aqueous suspension (milk of lime).
Uses
Faecesand urine disinfection within 2hrs ( by
mixing milk of lime)
Wall disinfection
As a deodorant lime is sprinkled in Cattle shed,
stables and urinals & latrines in public places.
385/3/2021Dr. Shubhangi Kshirsagar

39. 8. Ethylene oxide
Explosive, thus mixed with CO
2
Uses –
Heat sensitive articles –sterilize at 55-60
0
C
Kills bacteria, spores, viruses
Sterilization of fabrics, plastic equipment,
cardiac catheters, books; but the process is
difficult.
395/3/2021Dr. Shubhangi Kshirsagar

40. 9. Metals as microbicides
Antiinfectiveactivityofsomeheavy
metalsknownasAntiquity.
Ex.Silver–prophylaxisofconjunctivitisof
newborn,topicaltherapyforburnwound.
MetalssuchasSilver,Iron,Copperare
used forenvironmental control,
disinfectionofwater
405/3/2021Dr. Shubhangi Kshirsagar

41. 10. Miscellaneous inactivating agents
2. Microwave
Radio frequency waves -
2450MHz
Used for disinfection of
Soft contact lenses
Dental instrument
Urinary catheter
3. Ultra-violet radiation
Disinfection of drinking
water, air, titanium implants
1.Pasturization
4. Ozone
Drinking water disinfection
5. Flushing & washer
disinfectors
415/3/2021Dr. Shubhangi Kshirsagar

42. Thank you!
425/3/2021Dr. Shubhangi Kshirsagar