Microorganisms and Diseases

Learning Goals

  • Bacteria: Name the organism (genus species)
  • Protozoa: Name the Genus
  • Worms: Name the worm – common name
  • Virus: Name the disease

Key Bacteria

  • Clostridium botulinum: Causes foodborne botulism, muscle paralysis; found in improperly preserved foods.
  • Clostridium tetani: Causes tetanus; symptoms include lock jaw and muscle spasms; prevent with vaccine.
  • Clostridium difficile: Causes pseudomembranous colitis, associated with antibiotic use.
  • Bacillus anthracis: Anthrax, enters through skin or contaminated products.
  • Listeria monocytogenes: Causes listeriosis, found in contaminated foods, can cross placenta.
  • Streptococcus pneumoniae: Causes pneumonia, meningitis, otitis media; vaccines available.
  • Staphylococcus aureus: Produces toxins, causes foodborne illnesses, MRSA resistant strains

Key Protozoa

  • Giardia sp.: Causes diarrhea, spread through contaminated water.
  • Trypanosoma sp.: Causes Chagas disease, spread by kissing bugs.
  • Plasmodium sp.: Causes malaria, transmitted by mosquitoes.

Key Worms

  • Ascaris sp.: Common intestinal roundworm parasite.
  • Toxocara sp.: Causes toxocariasis, commonly affects children.
  • Hookworm: Transmitted through contaminated soil, causes anemia.
  • Pinworm: Most common worm infection in the U.S.; primarily affects children.

Key Viruses

  • Smallpox: Eliminated via vaccination; causes rashes, spreads via respiratory droplets.
  • Herpes Simplex: Two types; causes oral and genital herpes; can remain dormant.
  • HPV (Human Papillomavirus): Causes warts and some cancers; preventable by vaccination.
  • HIV: Causes AIDS; transmitted through body fluids; manageable with ART.
  • Norovirus: Leading cause of foodborne illness and gastroenteritis, common in outbreaks.

Key Fungi

  • Candida albicans: Causes candidiasis; overgrowth can occur post-antibiotics.
  • Cryptococcus: Opportunistic fungal infection, particularly in immunocompromised persons.

Key Information on Prion Diseases

  • BSE (Mad Cow Disease): Transmitted through infected tissues; results in dementia and death.