By: Hibah A. W. Abusulaiman Second year Lab Medicine (Females) A.H. / Microbiology Practical (Course I)

Once upon a time… Please don’t sleep

Fashionable friends

Abrar’s…

Sara started the preparation early

She got a luxurious manicure and padicure plus…

An elegant evening gown

Lubna started the preparation 2 days before the wedding

She got an elegant evening gown, but…

A poor manicure and padicure

Both attended the wedding in…

After 45 days, Lubna was suffering from…

Diagnosed as Hepatitis Patient

After discussion with the Doctor, she knew it’s because of the poor hygienic manicure and pedicure

Good hygienePoor hygiene

Destruction of Microorganisms

So, do you think we are in a war with…?!

Simply because they are the agents of… Contamination, infection and decay

Early civilization

In the 1800s Aseptic techniques invented to prevent contamination of surgical wounds

Many organizations classified infection control systems and substances into: Physical methods. Chemical methods. Referred broadly as Germicides

Germicidal systems fall into three categories: 1.Decontamination. 2.Disinfection. 3.Sterilization.

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.

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.

3. Sterilization The complete elimination of viable organisms including spores. The highest level of control

Factors influencing disinfection Number of microorganisms. Species and type of microorganism. Temperature.

Destruction of Microorganisms Physical Antimicrobial Agents Chemical Antimicrobial agents

Physical Antimicrobial Agents Physical environmental agents can destroy large concentrations of microorganisms in lab cultures or a clinical specimen.

Physical Antimicrobial Agents Physical sterilization Dry heatMoist heatIncineration Osmotic pressure FiltrationRadiation

UV Light To inactivate microorganisms on surfaces

Filtration Filtration is used to remove bacteria, fungi and their endospores from air or solutions.

Osmotic Pressure Extremely hypertonic conditions can cause plasmolysis.

Incineration

Autoclave Moist heat- Steam sterilization 121 O C for 15 min

Dry heat 160 O C for 2 hours OR 170 O C for an hour

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).

Desinfectants ViricidalFungicidalSporicidalBctericidalDisinfectant goodGoodPoorGoodEthyl and isopropyl alcohols Good Chlorine Disinfectants Good Formaldehyde and Glutaraldehyde Good Hydrogen peroxide Good PoorGoodIodophors

Evaluating a disinfectant Direct spray method. Testing the quality of disinfectant from different brands.

5 mL Bacterial Suspension in Nutrient Broth (Control) 5 mL Dettol 5 mL DAC 5 mL Gento 5 mL Clorox Testing Disinfectant from Different Brands 0.5 mL

Bacteria in Clorox Testing Disinfectant from Different Brands Bacterial Suspension in Nutrient Broth (Control) Bacteria in Dettol Bacteria in DAC Bacteria in Gento Water Bath

Bacterial Suspension in Nutrient Broth (Control) Water Bath After 5min in Water Bath After 10 min in Water Bath After 20 min in Water Bath 48 hrs Incubation in the 37 O C Testing Disinfectant from Different Brands 2 Loopfulls

Observe the bacterial growth

Objectives Some infection control terms. Factors influencing disinfectants. Physical destruction of microorganisms. Chemical destruction of microorganisms. Methods of evaluating disinfectants.

Thank you for listening Any questions?!

Thank you for paying attention Any questions?!