DNA Viruses Flashcards
(85 cards)
What’s the only SS DNA virus?
Parvovirus
What is the important Parvovirus?
B19
Describe the proteins expressed by DNA viruses and the order they are expressed in
1) Interferons and proteins involved in immune evasion
2) Proteins that induce cell cycle progression (exception: Pox because it’s in cytoplasm and Parvo because it’s too small)
3) Structural proteins necessary to build new viral particles
Primary Herpes Infection
Usually the worst disease attack (if it’s symptomatic); instead of a single lesion there will be multiple
Treatment for CMV
Gancyclovir
Name the naked DNA viruses
PAPP Parvovirus Adenovirus Papillomavirus Polyomavirus
Tropism for adenovirus
mucosal epithelium (primary), lymphoid, mesenchymal
Second Line Antiviral drugs
These drugs do not require phosphorylation; they carry higher toxicity to host however. They include Cidofovir and Foscarnet
Describe the stability of Enveloped vs Naked viruses
Naked viruses are more capable of persisting in the environment and are resistant to chemical inactivation - more likely to lead to epidemic outbreaks
How can HSV-1 lead to Corneal Blindness and Encephaly?
Virus is latent in Trigeminal Ganglia, so if virus goes down V1 it can reach the eye. Alternatively, if the virus goes backwards along the nerve it can reach the Temporal Lobe of brain (usually only occurs in people who get many outbreaks a year)
Describe prevalence of CMV
CMV is widely dispursed throughout the population, and the vast majority of people are infected but remain asymptomatic. Most people get it during perinatal period or during reproductive years.
Molluscum Bodies
Acidophilic inclusions seen in epidermis due to an accumulation of virons of Pox virus
The worse disease associated with Gamma Herpes viruses is what?
Their latency phase - Cancer
Polyoma Viruses
- SV 40
- JC Virus
- BK Virus
- Merkel Cell Virus
Where do JC and BK viruses remain latent?
Kidney, lymphocytes, and brain
How Alpha herpes viruses evade immune system during latency phase
They produce NO PROTEIN during latency phase; only a small intron of RNA is expressed called the LAT Transcript
Name the Alpha Herpes Viruses
HSV 1, HSV 2, VZV
Diseases associated with HSV-2
- Genital infection
- Oral infection
- Congenital Herpes in Neonate (bad)
What DNA Viruses have circular DNA?
Papilloma Polyoma Hepadna
Replication Machinery encoded by DNA viruses
1) DNA-Dependent-DNA Polymerase
2) Thymidine Kinase
Hepadna encodes Reverse Transcriptase
Why do we care about the site of viral replication?
We know that if we see intranuclear inclusions it’s likely a DNA virus (exception: Pox), and if we see cytoplasmic inclusions it’s likely an RNA virus (exception: Influenza and Retroviruses)
Trophism of Varicella Zoster Virus
Immune Cells and Neurons, epithelial cells, T cells
Diagnostic important of Syncytia
If multi-nucleated giant cells are present it indicates the virus is enveloped
Name the Gamma Herpes viruses
EBV, HHV 8

