Unit 1 Microbes

Staphylococcus Areus (Gold)

Type: Bacteria, Gram (+), Cocoi

Disease: Skin infections w/ Pus, Boils, Impetigo (Around nose + mouth get red boils)

Pathogenesis: Break in skin allows for infection

• Production of toxins

  • Inhibit Phagocytosis, doesn’t allow WBC

  • Cause pus formation

  • Separate from dermis to epidermis

Treatment: Non-penicillin antibiotic (If MRSA), Vancomycin (last choice, can be resistant)

Candida Albicans

Type: Fungi, Dimorphic Yeast/Mold

Disease: Candidiasis (Yeast Infection), Thrush

Pathogenesis: Opportunist, can invade when immune system is weak, normal flora is killed due to antibiotics

Treatment: Topical antifungal cream, amphotericin

Giardia Lamblia

Type: Protozoa

Disease: Giardiasis - Diarrhea, inability to absorb fatty food

Pathogenesis: Cyst ingested and becomes trophozoite in small intestines

• Trophozoite attach to epithelial tissue → Inflammation

• Interferes w/ abruption of food and fluids causing diarrhea

  • Noticing change in environment can go back to being a cyst

Treatment: Metronidazole (anti-protozoan drug)

Enterobius Vermicularis “Verm:

Type: Helminth, Pin worm

Disease: Enterobiasis - Intestinal infection, nocturnal anal itch

Pathogenesis: eggs ingested and hatch in duodenum. Females emerge at night and lay eggs around anus → Itching

Treatment: Mebendazole (Oral Anti Helminth Drug)

Herpes Simplex Virus

Types: DNA Virus, enveloped

Disease: Cold sores - ulcerative lesion on gum or lips (Pus filled, bubbling, ulcerations)

Pathogenesis: Virus enters through oral contact w/ infected host.

• 80% of population has HSV1. can go dormant once infected

• Replicates in epithelial cells → Vesicles

• Rides up neuron and stays dormant until future outbreak

• When sick herpes will jump out the neuron and start showing on the face to find new host

Treatment: Acyclovir (Antiviral) before vesicles form (First sign of herpes, prevent vesicles from forming)

PrP3c Prion

Type: Prion

Disease: Creutzfeldt - Jakobs Disease (CJD)

• Degeneration of CNS → Dementia, abnormal motor function → Death

Pathogenesis: PrP3c (Misfolded protein) Converts a PrPc (Normal Protein) → Prpr3c

• Prp3c aggregate to form deposits in brain → Vacuoles

Treatment: None

Yersina Pestis

Type: Bacteria, Gram (-), rod

Disease: Plague - Fatal infection of lymph nodes (bubonic), or lungs (Pneumonic) Can lead to each other

Pathogens: Flea transmits bacteria during blood meal

• Bacteria phagocytized, carried by lymph node (protected by antiphagocytic antigen)

• lymph node swells → Bacteria into blood → other organs → can spread to lungs → Lungs get infected → Aerosolized travel via air and coughed out

Treatment: Streptomycin or doxycycline

Blackening of Skin = Dead Tissues

Bacillus Anthracis

Type: bacteria, Gram (+), rod

Disease: Anthrax

Pathogenesis: Endospores inhaled, ingested or enter skin

• Bacillus genus can become endospores, smaller, more protective

Inhaled or Ingested: Germinate in Lungs, capsule prevents phagocytosis (Able to evade immune system), release toxins → swelling necrosis (Tissue Death) → Death

Skin: Painless ulcers w/ a black center (Eschar) - Toxins that cause tissue death

Treatment: Penicillin - Work well w/ Gram (+) organisms (Penicillin Positive)

Treponema Pallidum

Type: Bacteria, Gram (-) spirochete

Disease: Syphilis - STI w/ characteristic stages

1. Primary: Painless ulcer at site of inoculation

2. Secondary: Swollen lymph node and skin rash (Chancre goes away)

3. Latent Stage: No Symptoms

4. Tertiary: Damage to heat, blood vessels, brain, eyes. Nose can collapse in w/ bone deterioration

Pathogenesis:

• Bacteria enters via Mucous membranes of genitalia → Lymph → Blood

• Bacteria disseminates to skin

• Evades immune system by slow dividing time (Able to not get detected)

• Invades rest of body

Treatments: Penicillin (Works even though Gram (-) usually (+)) or doxycycline (Oral Antibiotics)