Microbiology

Microbiology Study of very small life forms Most are not harmful Can’t see them with the eye Most are not harmful Used for Vitamins Antibiotics Some food products Yogurts cheese etc. Some are harmful Pathogens Disease causing micro-organisms Includes Bacteria, Viruses Protozoa Rickettsiae, Yeasts molds

Important people in Microbiology Anton Van Leeuwenhoek Ground lenses (glass) to magnify things Saw moving micro-organisms In plaque Wrote about findings. Father of Microbiology.

Important people in Microbiology Louis Pasteur Experimented w/ fermentation Proved bacteria causes disease. Proved heat killed bacteria and spores Work led to canned food. “Pasteurization” Heat product to kill germs. (Milk, beer)

Important people in Microbiology Robert Koch Proved specific bacteria causes specific diseases. Etiologic agent Aka causitive agent Developed Koch’s Postulates Steps to prove that bacteria caused disease.

Gram Stain Helps ID the group of bacteria Gram Positive Gram Negative Developed by Dr. Christian Gram Cells place on a slide Dye added Rinse w/ iodine Dry Rinse w/ water and acetone alcohol Cell is observed. Gram Positive Cell will appear: Dark purple Gram Negative To lose color Appear clear Appear “pink” not purple

Gram Stain

Bacteria Tiny Single celled Living organism Killed w/ antibiotics No chlorophyll molecule that absorbs sunlight Divide every 20 min. Warm Dark Moist Killed w/ antibiotics

Spores Spores Bacteria that has Sporulated or is Sporulating Resists Coats itself in Layers of protein Ensures survival Resists Drying / Heat Boiling Most chemicals radiation Used in autoclave “biological monitor”

Bacteria and Oxygen Aerobic Anaerobic Needs O2 to grow and live Most bacteria are aerobic Certain Neisseria Pseudomonas aeruginosa Staphylococcus, or staph Anaerobic Die with O2 Can only live without O2 Gram-negative anaerobes Porphyromonas (periodontitis) Gram-positive anaerobes Peptostreptococcus (oral infections)

Bacteria and Oxygen Facultative anaerobic bacteria Grow and live With or Without O2 They cause Oral and dental infections. Bacteremia bacteria in the blood stream Endocarditis. Inflammation inside layer of the heart.

Bacteria Morphology Cocci Bacilli Round Circular Spherical Rod streptococcus Bacilli Rod Straight Lactobacilli

Bacteria Morphology Spirilla Vibrous Spiral Spring Corkscrew C shaped Helicobacter pylori Vibrous C shaped Curved (comma) Vibrio cholerae

Bacteria arrangements Single Cell Pairs Clusters Chains Colonies (lg. clusters)

Bacterial diseases Tuberculosis Diphtheria Pertussis Tetanus Strep throat Pneumonia Rheumatic fever Staph infection Gangrene Toxic shock Venereal diseases Aka (STD’s) Chlamydia Anthrax

Protozoa Single celled animal life Live in fluids: Causes; Dysentery Aka ameoba Live in fluids: Blood Saliva Intestines Polluted water Pools ponds Causes; Dysentery Severe diarrhea Malaria Severe ‘flu’ Sleeping sickness Periodontal disease Found in: Plaque Perio pockets

Yeasts and molds Includes: Form of plant life Causes Treatment Bread yeast Mushrooms Bread molds Form of plant life No chlorophyll Cannot be killed w/ antibiotics. Used for Bacteria / protozoa Causes Candidiasis Aka thrush Fungal infection of: Mouth Vaginal area Treatment Anti-fungal drugs

Virus Smallest microorganism Needs a host cell to reproduce. Most are anaerobic Die w/ exposure to air. Not killed w/ antibiotics Polio Virus

Examples of viral infections Measles Rubella (German measles) Mumps Infection of the Parotid salivary glands Polio Chicken pox Cold Influenza (flu) Hepititis HIV AIDS

Routes of exposure Direct contact. Indirect contact. Inhalation Sneezing into an open mouth. Touching open sores. Indirect contact. Sneeze onto hand, touch door handle, next person touches handle. Inhalation Aspirating / breathing in.

How the body resists diseases 1st line of defense. Intact skin Sneezing Coughing Vomiting Diarrhea 2nd line of defense. Circulatory system Wbc’s delivered to area of infection. Inflammation 4 signs of inflammation Erythema (redness) Edema (swelling) Heat Pain

How the body resists diseases 3rd line of defense Antibodies Produce immunity from specific pathogens. Disease causing microorganism Antigen Pathogens that cause body to produce antibodies. Allergen An antigen that causes an over-reaction Can cause anaphylactic shock.

Immunity A person/bodies ability to resist a pathogen or disease. Two kinds Natural Born w/ it. Acquired Have to get it. Naturally Artificially

Acquired immunity Passive Active Antibodies from another person are injected into you. Immediate Short term 6 weeks Breast milk provides some passive immunity to baby Active Natural acquired Person gets a disease, body produces antibodies, should not get disease again. Artificial acquired Immunization Antigen is injected Antibodies are produced

Conclusion Understanding the disease process and how it affects the human body is very important. You are the “expert”! Don’t ever diagnose! When in doubt…ask questions. Any questions?????????