Disease and Disease-Producing Organisms

Disease and Disease-Producing OrganismsChapter 5Objectives

Define disease and list seven categories of disease List 7 predisposing causes of disease Define terminology used in describing and treating disease Define complementary and alternative medicine and give examples Explain methods by which microorganisms can be transmitted List 4 types of organisms studied in microbiology and give characteristics List some diseases caused by each type Define normal flora and explain the value Describe the 3 types of bacteria by shape List several diseases in humans caused by worms Give some reasons for the emergence and spread of microorganisms Describe several public health measures Differentiate between sterilization, disinfection and antisepsis Describe techniques included as part of body substance precautions List some antimicrobial agents and how they work Describe several methods used to identify microorganisms in the lab

What is disease?- It is an illness, an abnormal state in which part or all of the body does not function properly CATEGORIES - Infection - Degenerative - Nutritional - Metabolic - Immune - Neoplasms - Psychiatric

Predisposing Causes of Disease Age Gender Heredity Living conditions and habits Emotional disturbance Physical and Chemical damage Preexisting IllnessREMEMBER : A predisposing cause may not actually cause the disease, but increases the probability of a person becoming ill.The Study of Disease

DefinitionsPathophysiology Etiology Acute Chronic Subacute Idiopathic Iatrogenic Epidemiology Incidence Prevalence Mortality Epidemic Endemic Pandemic

Treatment and Prevention of Disease Diagnosis determination of the nature of the illness

Need to know symptom, sign, syndrome, prognosis, therapy and prevention

CAM is defined as methods of disease prevention and treatment used along with traditional medicine (Examples include: chiropractic, acupuncture, biofeedback) Infectious DiseaseMicroorganisms are the predominant cause of disease in the human body. Parasite organism that liveson or within a host at hosts expense

Pathogens Pathogens are disease causing organism and infection is an invasion of pathogens that have adverse effects

(An infection can be local or systemic.)

Opportunistic infection Communicable infection

Modes of Transmission Disease can be spread directly or indirectly.

Portals of entry : skin, respiratory, digestive, urinary and reproductive systems

MicrobiologyThe study of microorganisms

*** Bacteria, Viruses, Fungi, Protozoa

BacteriaSingle-cell organism whose genetic material is not enclosed in a membrane. (No true nucleus) Can grow with or without oxygen Resistant forms are called endospores Flagella Pili

Bacteria cont. Shape and Arrangement : Cocci, Bacilli, Curved rods

Others : Rickettsia and Chlamydia

Diseases caused by bacteria : Pneumonia, Tuberculosis, Syphilis, Lyme disease, TyphusVirusesObligate parasite that can only reproduce in living cells. Contain genetic material. Not susceptible to antibiotics.

Classified according to the type of nucleic acid they contain (DNA or RNA) and the type of disease they cause.

Named according to where they were isolated, the symptoms they cause, the host, or the vector that carries them.

Viruses cont. Prions and Viroids

Much smaller than bacteria

Diseases caused by viruses : Measles, Influenza, Chickenpox, Common ColdFungiSimple plant-like organism. 2 types : Yeasts and Molds

Yeast single cell

Mold filamentous

Diseases caused by fungi : Ringworm, Thrush, Pneumonia

ProtozoaSingle-cell, animal-like microbes Amebas Ciliates Flagellates Sporozoa What you will see: Giardia (Flagellate)

Parasitic WormsThey are parasites with human hosts

Roundworms (ascaris,pinworms, hookworms) Flatworms (tapeworms, flukes) Infection by worms is called infestation.

Microbial ControlInfectious disease increasing due to various factors. Increased population & travel, disruption of animal habitats, changes in food handling Microbes and Public Health : sewage and garbage, water purification, prevention of food contamination, milk pasteurization Aseptic Methods : sterilization, disinfection, antisepsisInfection Control HANDWASHING. HANDWASHING. HANDWASHING. Universal techniques, sharps safety, specific precautions OSHA Antimicrobial Agents : antibiotics, antiviral, antifungal, antiparasitic ANTIBIOTICS/MRSA Antibiotic is used to kill bacteria. Derived from fungi and soil bacteria. Usage can be harmful Antibiotic-resistance

Lab Identification of PathogensBlood, Spinal Fluid, Feces, Urine, and Sputum most frequently studied. Bacterial Isolations and Tests Staining Techniques Other techniques

Freebie What will you see clinically : - Know antibiotics - MRSA - Infection Control