1 Microbiology DA 116 Infection Control

2 Study of microorganisms –Small living organisms Important to know –Pathogens = disease-causing microorganisms Also called microbes –Prevent transmission of disease through infection control Study of microorganisms –Small living organisms Important to know –Pathogens = disease-causing microorganisms Also called microbes –Prevent transmission of disease through infection control

3 Helpful or Harmful? Equally: –Helpful = non-pathogenic Ex. Food products: Aged cheeses, wines, yogurt Ex. Soil fertilization, production of life-saving drugs –Harmful = pathogenic Ex. Infectious diseases Dental Health Concerns –Dental caries = bacteria (streptocoocus mutans) –Periodontal disease = bacteria + protozoa Equally: –Helpful = non-pathogenic Ex. Food products: Aged cheeses, wines, yogurt Ex. Soil fertilization, production of life-saving drugs –Harmful = pathogenic Ex. Infectious diseases Dental Health Concerns –Dental caries = bacteria (streptocoocus mutans) –Periodontal disease = bacteria + protozoa

4 Bacteria Protozoa Fungi Viruses Bacteria Protozoa Fungi Viruses

5 Bacteria Singular = bacterium Good and bad Can live independently under favorable environmental conditions –98.6°, dark, moist Some types require oxygen to grow and survive –Aerobic Singular = bacterium Good and bad Can live independently under favorable environmental conditions –98.6°, dark, moist Some types require oxygen to grow and survive –Aerobic

6 Bacteria: classified by shape Cocci (sometimes described as spherical-shaped) –Chain-shaped Streptococci –Strep throat, tonsillitis, pneumonia, endocarditis –Cluster-shaped Staphylococci –Boils, skin infections, pneumonia, endocarditis Bacilli –Rod-shaped –Tuberculosis Spirochetes (spirilla) –Spiral-shaped –Lyme disease, syphilis Cocci (sometimes described as spherical-shaped) –Chain-shaped Streptococci –Strep throat, tonsillitis, pneumonia, endocarditis –Cluster-shaped Staphylococci –Boils, skin infections, pneumonia, endocarditis Bacilli –Rod-shaped –Tuberculosis Spirochetes (spirilla) –Spiral-shaped –Lyme disease, syphilis

7 Bacterial Spores Most resistant form of life known –Harmless spores used to test sterilization techniques in infection control Caused by unfavorable conditions Alive, but inactive –Cannot reproduce or cause disease If conditions improve, become active and disease- causing Examples: –Tetanus, tuberculosis, strep throat Most resistant form of life known –Harmless spores used to test sterilization techniques in infection control Caused by unfavorable conditions Alive, but inactive –Cannot reproduce or cause disease If conditions improve, become active and disease- causing Examples: –Tetanus, tuberculosis, strep throat

8 Protozoa One-celled organisms Do not cause disease Live in hosts which can cause disease –intestinal infections –invade blood, lungs, liver or brain Not usually dental office infection control concern One-celled organisms Do not cause disease Live in hosts which can cause disease –intestinal infections –invade blood, lungs, liver or brain Not usually dental office infection control concern

9 Fungi Plants –Mushrooms, yeasts, molds Candidiasis –Common yeast found throughout body –Opportunistic Affect very young, very old, or very ill patients Oral candidiasis –white membranes on tissues throughout oral cavity –common under dentures

10 Viruses Tiny disease-causing organisms Live and multiple only inside a host –Human, animal, plant, or bacteria –Invades host cell, replicates, and destroys host cell allowing virus cells to release into the body Great concern to DHCW Tiny disease-causing organisms Live and multiple only inside a host –Human, animal, plant, or bacteria –Invades host cell, replicates, and destroys host cell allowing virus cells to release into the body Great concern to DHCW

11 Characteristics of Viruses Specificity: –some live only in certain cells HIV –others affect only certain organs Mumps = thyroid, pancreas, testicles, ovaries) Latency: –Can be dormant for years and then reactivate HIV and Hepatitis C “carriers” (3-5% of adults with HBV) Dental Office Concern = herpes simplex –HSV 1 = lips, mouth, face –HSV 2 = genital area –Both can be found in oral or genital areas Specificity: –some live only in certain cells HIV –others affect only certain organs Mumps = thyroid, pancreas, testicles, ovaries) Latency: –Can be dormant for years and then reactivate HIV and Hepatitis C “carriers” (3-5% of adults with HBV) Dental Office Concern = herpes simplex –HSV 1 = lips, mouth, face –HSV 2 = genital area –Both can be found in oral or genital areas

12 Treatment and Transmission of Viruses Treatment: –Viruses can mutate to adapt to new situations –only symptoms, not infective cause (virus) –Immunization EVERY year Infection control: easy to destroy in external environment Transmission –Direct contact –Indirect contact –Insects –Contaminated food or water Treatment: –Viruses can mutate to adapt to new situations –only symptoms, not infective cause (virus) –Immunization EVERY year Infection control: easy to destroy in external environment Transmission –Direct contact –Indirect contact –Insects –Contaminated food or water

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14 Viral Hepatitis Inflammation of the liver Five types –HAV Hepatitis Afood-borne (fecal/oral) immunization –HBV Hepatitis Bblood-borneimmunization –HCV Hepatitis C blood-borne –HDV Hepatitis D occurs in HBV or HCV carrier » (HBV immunization protects against HDV) –HEV Hepatitis E food or water-borne (fecal/oral) Latency –HAVoutside body for months –HBV7 days and still transmit infection –HCV16 hours – 4 days still transmit infection Inflammation of the liver Five types –HAV Hepatitis Afood-borne (fecal/oral) immunization –HBV Hepatitis Bblood-borneimmunization –HCV Hepatitis C blood-borne –HDV Hepatitis D occurs in HBV or HCV carrier » (HBV immunization protects against HDV) –HEV Hepatitis E food or water-borne (fecal/oral) Latency –HAVoutside body for months –HBV7 days and still transmit infection –HCV16 hours – 4 days still transmit infection

15 Transmission of Hepatitis Viruses HAV and HEV –Fecal/oral Contaminated food and water Handwashing and clean food preparation methods HBV and HCV –Bloodborne –Contaminated needles or sharps injuries –Sharing needles –Tattoos from contaminated needles or instruments –Infected mothers to newborns HDV –Must have had HBV or HCV in the past HAV and HEV –Fecal/oral Contaminated food and water Handwashing and clean food preparation methods HBV and HCV –Bloodborne –Contaminated needles or sharps injuries –Sharing needles –Tattoos from contaminated needles or instruments –Infected mothers to newborns HDV –Must have had HBV or HCV in the past

16 HIV Human immunodeficiency virus –Body’s immune system breaks down Symptoms can include –fatigue, weight loss, fever and sweats, skin rashes, short term memory loss HIV patient can remain healthy for years Routes of transmission –Blood, semen, vaginal fluids, breast milk AIDS –Acquired immunodeficiency syndrome –Caused by HIV related serious illnesses and infections Human immunodeficiency virus –Body’s immune system breaks down Symptoms can include –fatigue, weight loss, fever and sweats, skin rashes, short term memory loss HIV patient can remain healthy for years Routes of transmission –Blood, semen, vaginal fluids, breast milk AIDS –Acquired immunodeficiency syndrome –Caused by HIV related serious illnesses and infections

17 Always follow Standard Precautions! Remember: –You cannot know which patients have some sort of infectious disease by Looking at them Talking to them Reading their medical history forms Even if they are your family or friends Because: –Symptoms don’t always appear until after you’ve treated the patient, yet the patient can be contagious! –Symptoms in the blood aren’t visible at all! Remember: –You cannot know which patients have some sort of infectious disease by Looking at them Talking to them Reading their medical history forms Even if they are your family or friends Because: –Symptoms don’t always appear until after you’ve treated the patient, yet the patient can be contagious! –Symptoms in the blood aren’t visible at all!