Nature of Micro-

organisms

Controlling Infection -

Microorganisms• What are they?– Tiny organisms found in the air, on our skin, in our

food, and on everything we touch that you cannot see without a microscope

• Good– Nonpathogenic, keep a balance in our

environment• Bad– Pathogenic, cause illness, infection, or disease

Microorganisms• Anaerobic–Able to grow and function without

oxygen• Aerobic–Require oxygen to survive

Microorganisms• Most that cause illness like warm

temperatures (like the body temp) • All need moisture• Most prefer a dark area to grow

What organisms in biology class like the same things?? Mold and Fungus

Microorganisms• Nonpathogenic Organisms– Used for good things like making foods and

beverages– Decompose organic material in nature– Breakdown food elements in the digestive system– Help control the growth of pathogenic organisms

Microorganisms• Pathogenic Organisms– When organisms leave their normal environment

in the body and move into other areas and become harmful

– Examples:• E.coli• Salmonella• Bacteria – Staph • Viruses

Microorganisms• Conditions Affecting the Growth of Bacteria

1. Food – bacteria grow well in the

food left in a patient’s room

2. Moisture – bacteria grow well in moist places

Microorganisms• Conditions Affecting the Growth of

Bacteria3. Temp • 170 degrees F - kills most bacteria

• 50-110 degrees F - most disease causing bacteria grow rapidly

• 98.6 degrees F – normal human body temp where bacteria can thrive easily

• 32 degrees F – low temperatures slow their activity and growth rate

• Conditions Affecting the Growth of Bacteria4. Oxygen

- Aerobic – need oxygen- Anaerobic - don’t need oxygen

5. Light- Darkness – bacteria become active and multiply- Light – when exposed to direct sunlight bacteria become sluggish and die rapidly

6. Dead and Living Matter- Saprophytes – bacteria that live on dead matter or tissues- Parasites – bacteria that live on living matter

Microorganisms

• How they affect the body

- Produce toxins - Food poisoning causes fatigue, diarrhea, and vomiting

- Tetanus toxins cause damage to the nervous system

- Histamines cause allergic reactions like runny noses or more severe such as anaphylactic shock

Microorganisms

• How they are spread

1. Direct contact

2. Indirect Contact

3. Airborne

4. Oral Route

5. Insects and Pests

Microorganisms

• How do we protect from them?

- Standard Precautions and Transmission-Based Precautions- Will cover later

Microorganisms

• Signs and Symptoms of an Infection

- Generalized (example: cold and flu)- Headache, fatigue, fever, increased pulse and

respiration

- Localized (staph infection)- Redness, swelling, heat, possible drainage, pain

Microorganisms

• So what is the point???

- Microorganisms are all around us.

- Some are good and some are bad

- We need to understand them and how they spread to

protect ourselves and our patients

- Learn how to control and treat them

- As a healthcare worker it is your responsibility to practice

good techniques to prevent the spread of infection

Microorganisms