(Q4) Prions and Dermotropic Viruses (Ch. 27) Flashcards
Prions
- Small, proteinaceous, infectious, particles that are resistant to most procedures that modify nucleic acids.
- Obligate intracellular parasites
- Nonliving agent
Why are prions dangerous to the embalmer?
- They resist inactivation by heat, formaldehyde, Ultraviolet light, and ionizing radiation
- Not destroyed by proteases or nucleases
(Transmissible) Spongiform Encephalopathies
- Diseases caused by prions
- neurodegenerative brain disorders (that cause the brain to look like a” sponge”)
What is a common denominator of all prion disorders?
- Amyloid Deposits
Amyloid
A general term for any intracellular starch-like protein deposit
Creutzfeldt-Jakob Disease (CJD)
- A degenerative brain disorder that leads to dementia and death
- Disorder is caused by a prion
- Can occur spontaneously, be genetic, or be transmitted through contact with contaminated tissue
- Affects 1/1 Million people
Dermotropic Viruses
- Viruses that manifest themselves as lesions on the skin
- Rubeola Virus
- Rubella Virus
- Varicella Zoster Virus
- Herpes Zoster Virus
- Herpes Simplex-1
- Herpes Simplex-2
- Smallpox Virus
- (Monkeypox Virus)
Rubeola Virus
- Measles Virus
- Highly contagious disease
- A type of pox virus
- causes skin lesions and rashes, oral lesions
- Effective Vaccine: MMR vaccine
Rubeola Virus Portal of Entry and Exit
Respiratory Tract
Rubeola Virus Mode of Transmission
Droplet Transmission
What are the oral lesions caused by the Rubeola Virus?
Koplik’s Spots
Rubella Virus
- German Measles, 3-Day Measles
- Milder form of measles
- Causes skin lesions and rashes
- Is able to cross the placenta and cause congenital rubella
Rubella Virus Portal of Entry and Exit
- Respiratory Tract
- Placenta
Rubella Virus Mode of Transmission
- Direct: Droplet Transmission
- Indirect: Congenital
Varicella Zoster Virus
- Chickenpox
- A herpes virus
- Causes skin lesions and rashes
- Serious complications associated with younger children (Reye’s Syndrome)
Herpes Zoster Virus
- Shingles Virus
- Reactivation of the dormant Varicella Zoster Virus
- A herpes virus
- Usually affects older people
Varicella Zoster Virus/Herpes Zoster Virus Portal of Entry and Exit
- Respiratory Tract
Varicella Zoster Virus/Herpes Zoster Virus Mode of Transmission
- Droplet Transmission
Herpes Simplex-1 Virus
- Cold Sores
- Causes oral lesions (cold sores and fever blisters)
- Type of herpes virus
Herpes Simplex-1 Virus Portal of Entry and Exit
- Mucous Membranes
- Broken Skin
Herpes Simplex-1 Virus Mode of Transmission
- Direct: Lesions touch Broken Skin
- Direct: Fluid transmission (saliva)
Herpes Simplex-2
- Genital Herpes
- Causes genital lesions
- Type of herpes virus
Herpes Simplex-2 Virus Portal of Entry and Exit
- Genital
- Placenta/Birth Canal
Herpes Simplex-2 Virus Mode of Transmission
- Direct: Sexual Contact
- Indirect: Congenital through placenta or birth canal
What is an important characteristic about herpes viruses?
- These viruses have reactivation potential
- Can infect someone, lay dormant in the body for long periods of time, before reappearing
Variola Virus
- Smallpox
- The first vaccine created was for smallpox
- First pathogen related disease that is considered “extinct”
Variola Virus Portal of Entry and Exit
- Respiratory Tract
Variola Virus Mode of Transmission
- Droplet Transmission
What do many of the deratropic virus’s have in common?
All of them except for Herpes Simplex 1 and 2 have the respiratory tract for portal of entry/exit and droplet transmission for mode of transmission
