Mcb 4 Flashcards
(30 cards)
What leads to secondary viraemia during the pathogenesis of poxvirus?
Virus multiplies further in seeded lymph nodes
This process can lead to another dermal inoculation and characteristic skin eruption (Pocks).
What occurs after the acquisition of poxvirus?
Poxvirus replication occurs locally in the infected cells, manifesting as dermal hyperplasia and leukocyte infiltration
This is followed by primary viraemia.
How does dissemination of poxvirus occur?
Dissemination occurs via lymphatics and cell (macrophages) mediated spread.
What is the mode of transmission for smallpox virus?
Smallpox virus transmission is respiratory.
What are the modes of transmission for other poxviruses?
Other poxviruses are largely transmitted by contact and zoonotic transmission is common.
What are the late proteins synthesized during poxvirus replication?
Late proteins include structural proteins.
What is the percentage of mature virus released by cell rupture?
80-90% are released by cell rupture.
What synthesizes early mRNA in poxvirus replication?
Virally-encoded RNA polymerase (prepackaged).
What are the early proteins formed from early mRNA?
- DNA polymerase
- Thymidine kinase
- Recombinase
What initiates the uncoating process of poxvirus?
Initial uncoating is due to cellular enzymes.
What does the viral core release during replication?
- Viral DNA
- Viral enzymes
What are the two types of gene products controlling viral replication?
- Early (Pre-replicative) gene products
- Late (Post-replicative) gene products
What must occur before viral replication can begin?
Attachment and penetration, followed by viral and host cell membrane fusion.
Are naked DNA viruses infectious?
Naked DNA is not infectious.
What are the strictly human viruses mentioned in the epidemiology of poxviruses?
- Small pox
- Molluscum contagiosum
What are the natural hosts for other poxviruses?
Vertebrates other than humans.
What are the zoonotic transmission methods for poxviruses?
- Accidental inoculation
- Occupational hazard
What disease does molluscum contagiosum cause?
Multiple and long-lasting skin nodules.
What is the primary host for the smallpox virus?
Humans.
What is a complication of cowpox?
Encephalitis may complicate cowpox.
What is the most important clinical indicator for diagnosing poxvirus infections?
Medical history.
What diagnostic methods are used for definitive diagnosis of poxvirus infections?
- Electron microscopy
- ELISA
- Serology
- IFA
- Viral isolation by culture
- PCR
What is the primary treatment approach for poxvirus infections?
Supportive treatment directed at symptoms.
What is the major tool for the prevention of smallpox?
Vaccination.
