Infectious Disease and Pathogen Transmission Notes

  • Microorganisms and Pathogenic Agents

    • Diseases are caused by infectious agents, including:
    • Bacteria
    • Protozoa
    • Viruses (noted as "virates" in the transcript).
    • Some pathogens cannot be cultured in the lab due to dependence on living hosts (e.g., liver cells).

  • Isolation Techniques

    • Reference to culturing bacteria using techniques such as yogurt fermentation, which involves lactobacillus.
    • Importance of knowing how certain pathogens (e.g., Neisseria) can evade immune responses by affecting key components like C3 in the complement cascade.

  • Exoenzymes and Nutrient Absorption

    • The role of exoenzymes in breaking down larger molecules (glucose, starches, glycogen) for absorption by pathogens.
    • Connective tissue matrix and its components:
    • Cells
    • Fibers
    • Ground substance (e.g., hyaluronic acid).

  • Blood Coagulation

    • Coagulase prevents blood clotting by countering coagulation processes.
    • Kinase activates anticoagulating hormones and enzymes to keep capillary blood fluid.

  • Disease Transmission

    • Pathogens exit host via portals (e.g., respiratory secretions, nasal mucus).
    • Transmission routes are categorized into three main types:
    • Contact: Direct or indirect (e.g., surface contact after someone coughs).
    • Vehicle: Transmission through contaminated items, water, or food.
    • Vector: Typically involves living organisms (e.g., mosquitoes transmitting malaria).

  • Epidemiology Terms

    • Incidence: The number of new cases of a disease over a specific period.
    • Prevalence: The expected number of existing cases in a population at a given time.
    • Sporadic: Few cases occur in a region; occasional cases.
    • Endemic: Disease consistently present within a given area or population (e.g., Rocky Mountain spotted fever).
    • Epidemic: When cases occur at a higher rate than normally expected in a specific region.
    • Pandemic: An epidemic that spreads over multiple continents (e.g., cholera).

  • Disease Reporting

    • Notifications about diseases are typically categorized as national or local, with different regulations for tracking and reporting.