Lab2 Destruction of microbes

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  • 1. Second year Lab Medicine (Females) 1433- 1434 A.H. / 2012- 2013 Microbiology Practical (Course I)• By: Hibah A. W. Abusulaiman
  • 2. Once upon a time… Please don’t sleep
  • 3. Fashionable friends
  • 4. Abrar’s…
  • 5. Sara started the preparation early
  • 6. She got a luxurious manicure and padicure plus…
  • 7. An elegant evening gown
  • 8. Lubna started the preparation 2 days before the wedding
  • 9. She got an elegant evening gown, but…
  • 10. A poor manicure and padicure
  • 11. Both attended the wedding in…
  • 12. After 45 days, Lubna was suffering from…
  • 13. Diagnosed as Hepatitis Patient
  • 14. After discussion with the Doctor, sheknew it’s because of the poor hygienic manicure and pedicure
  • 15. Good hygiene Poor hygiene
  • 16. Destruction of Microorganisms
  • 17. So, do you think we are in a war with…?!
  • 18. Simply because they are the agents of… Contamination, infection and decay
  • 19. Early civilization
  • 20. In the 1800s Aseptic techniques invented toprevent contamination of surgical wounds
  • 21. Many organizations classified infectioncontrol systems and substances into:• Physical methods.• Chemical methods. Referred broadly as Germicides
  • 22. Germicidal systems fall into three categories:1. Decontamination.2. Disinfection.3. Sterilization.
  • 23. 1. Decontamination:• Reduction of pathogenic microorganisms to be safe to handle without protective attire.• The Lowest level of control.• Includes physical cleaning with soap and detergents and removing of most organic and inorganic materials.• It is the critical step toward disinfection and steilisation.
  • 24. 2. Disinfection:• Disinfectants are liquid chemical agents that kill targeted pathogens but not spores . It can also be solid or gaseous.• It is the next level of control.
  • 25. 3. Sterilization• The complete elimination of viable organisms including spores.• The highest level of control
  • 26. Factors influencing disinfection• Number of microorganisms.• Species and type of microorganism.• Temperature.
  • 27. Physical ChemicalAntimicrobial Antimicrobial Agents agents Destruction of Microorganisms
  • 28. Physical Antimicrobial Agents • Physical environmental agents can destroy large concentrations of microorganisms in lab cultures or a clinical specimen.
  • 29. Physical Antimicrobial Agents Dry heat Moist heat Radiation Physical sterilization Incineration Filtration Osmotic pressure
  • 30. Radiation UV LightTo inactivate microorganisms on surfaces
  • 31. Filtration •Filtration is used to remove bacteria, fungi and their endospores from air or solutions.
  • 32. Osmotic Pressure• Extremely hypertonic conditions can cause plasmolysis.
  • 33. Incineration
  • 34. AutoclaveMoist heat- Steam sterilization 121OC for 15 min
  • 35. Dry heat160OC for 2 hours OR 170OC for an hour
  • 36. Chemical Antimicrobial Agents• In considering their application to patient care, two general classes: 1. Those destroying pathogenic microorganisms in the environment (disinfectants) or on skin (antiseptics). 2. Those administered to patients for treatment of infectious diseases (antimicrobial agents, often called antibiotics).
  • 37. Desinfectants Disinfectant Bctericidal Sporicidal Fungicidal Viricidal Ethyl and Good Poor Good good isopropyl alcohols Chlorine Good Good Good Good DisinfectantsFormaldehyde Good Good Good Good andGlutaraldehyde Hydrogen Good Good Good Good peroxide Iodophors Good Poor Good Good
  • 38. Evaluating a disinfectant• Direct spray method.• Testing the quality of disinfectant from different brands.
  • 39. Testing Disinfectant from Different Brands 0.5 mL 5 mL Bacterial 5 mL Clorox 5 mL DAC 5 mL Gento 5 mL DettolSuspension in Nutrient Broth (Control)
  • 40. Testing Disinfectant from Different Brands Water BathBacterial Suspension in Nutrient Bacteria in DAC Bacteria in Gento Bacteria in Dettol Broth (Control) Bacteria in Clorox
  • 41. Testing Disinfectant from Different Brands 2 Loopfulls 48 hrs Water Bath Incubation in the 37O C After 5min After 10 min in After 20 min inBacterial Suspension in in Water Bath Water Bath Water BathNutrient Broth (Control)
  • 42. Observe the bacterial growth
  • 43. Objectives• Some infection control terms.• Factors influencing disinfectants.• Physical destruction of microorganisms.• Chemical destruction of microorganisms.• Methods of evaluating disinfectants.
  • 44. Thank you for listening Any questions?!
  • 45. Thank you for paying attention  Any questions?!