Final; Herpesvirus and Papillomavirus Flashcards
What are the key characteristics of alphaherpesvirus
variable host range short reproduction cycle rapid spread in culture efficient destruction of infected cells capacity for latency
How is HSV-1 alphaherpesvirus transmitted
oral to oral
oral to genital
nearly 2/3 of adults are seropositive
How is HSV-2 alphaherpesvirus transmitted
genital to genital (some oral to genital)
prevalent with sexual activity
1/5 of adults are infected
Which cells does the HSV primarily infect
epithelial cells in the skin or mucosa; mucosa is more susceptible
What is the incubation time of HSV
2-14 days
typically 4-5 days
What are the symptoms of a HSV infection
flu-like; localized lesios
only 1/3 show symptoms with the asymptomatic still able to transmit
What is the duration of a HSV infection
8-12 days
How does HSV induce latency
the genome circularizes in stationary cells and stays as an episome in the nucleus
peripheral ganglia common
a stressful trigger can induce replication
What is required to combat the alphaherpes virus
cell mediated immune response
What strategies are used to prevent and treat alphaherpes infections
avoid contact during active herpes recurrence
Acylovir can be used to eliminate latent infections
What kind of host range does beta and gamma herpes virus have
restricted host range
What kind of reproductive cycle and progression does beta herepes have
longe reproductive cycle
sloe progression in cell culture
What does betaherpes do to the host cell
causes enlargement of infected cells; cytomeglia (CMV)
Where can you find the latent infection of beta herpes
in a variety of cells
What does gamma herpes target and causes what
T and B lymphocytes
lytic infections, latency in lymphoid tissue
Epstein Barr virus (EBV)
This virus is associated with carcinoma
EBV
This is a common childhood cancer in Africa caused by EBV
Burkett’s lymphoma
This is caused by EBV and can cause nodular sclerosing, mixed cellularity, or lymphocyte depletion
Hodgkin’s lymphoma
What are the three methods of immune evasion that beta/gamma uses
intrinsic
innate
adaptive
This persists in hematopoietic progenitor cells and macrophages; is a chronic persistent infection; controlled by healthy, active immune system
CMV
This persists in the genome of B cells, it ensures B cell proliferation and its genome replication
EBV
How are beta/gamma herpes treated
usually self-limiting
antivirals
immunoprophylaxis
there is no vaccine
What is the genome type of HPV
circular dsDNA
What is the virion of HPV
non-enveloped
How is HPV transmitted
direct skin to skin contact; it gains access through skin abrasions
How does HPV replicate in the skin
establish infection in basal layer
needs cells polymerase
virus is produced in differentiating cells
non-lytpic, virus spread with dead skin shedding
What makes HPV so hard to get rid of
its very hearty to environmental stress, allows transmission through fomites
What are the symptoms of HPV
warts at site of infection; 50% regress on own
What is the rare symptom of HPV
respiratory papillomatosis; can be lethal
What causes HPV to proliferate into cervical cancer
E7 blocks Rb = continued cell proliferation
E6 blocks p53 tumor supressor pathway
actual path unknown
What are the treatments/prevention strategies of HPV
ablative treatment (laser, surgery, chemicals, etc.) vaccination; Gardisil
