Exam Prep Notes: Microbiology and Infectious Diseases

Vaccines and Public Health

  • Previously Discussed Concepts: Phyllobacterium latum and asphyxia were mentioned in previous discussions related to vaccines.
  • Core Vaccine Principles: Discussions included herd immunity, vaccine efficacy, and adverse effects of vaccines.
  • Early Age Vaccination: Vaccination starts at a very young age to provide protection early in life, which also extends to later in life.
  • Side Effects vs. Population Protection: While side effects can occur, vaccines are often rolled out if they protect a significant majority, for example, if 90\text{ percent} of the population is protected even if 10\text{ percent} experience some side effects.

Parasitic and Bacterial Infections

  • Trichinosis: This is the only parasite discussed that is found specifically in muscles, such as the triceps or chest.
  • Cholera: Key symptom is voluminous rice water stool.
  • Hemolytic Uremic Syndrome (HUS):
    • Caused by Shiga-like toxin.
    • Associated with the E. Coli strain O157:H7.

Viral Infections

  • Respiratory Syncytial Virus (RSV):
    • While people of all ages can be prone to RSV, the risk of severe complications is significantly higher in specific populations.
    • High-Risk Groups: Babies and infants (especially those less than 6 months old) and the very old. Children aged 2\text{-}5 years also have a high incidence rate.

Post-Streptococcal Complications

  • A single streptococcal bacterial infection (e.g., tonsillitis as the primary infection) can lead to three significant issues:
    • 1. Rheumatic Fever: This occurs when bacteria damage or eat up the heart valves. This is not a primary infection of the heart but a secondary complication, nor is it a viral infection. It is a very common and medically important condition.
    • 2. Post-streptococcal Glomerulonephritis (Post-strep GN): This complication involves immune complex buildup in the kidneys, leading to kidney damage after a strep infection. GN stands for glomerulonephritis.
    • Total Issues: Including the primary infection (tonsillitis), one strep bacteria can lead to a total of 4 issues.

Other Infections and Diseases

  • Dengue Fever: Mentioned alongside hemorrhagic fever, indicating it can be part of this group of diseases.
  • Staphylococcus Epidermidis: The term epidermidis refers to the skin. This bacterium is frequently associated with infections resulting from skin breakage or the use of catheters.
  • Polio: No longer present in the country, suggesting successful eradication or control efforts.
  • Mad Cow Disease (Bovine Spongiform Encephalopathy):
    • Originates from cows.
    • The equivalent disease in humans, spread by humans, is Creutzfeldt-Jakob disease.