Flashcards in Virus Pathogenesis Deck (19)
What are 3 virus pathogenic mechanisms?
-cell destruction following virus infection
-virus induced changes to cellular gene expression (cellular transformation by tumour viruses)
What is an example of cell destruction following viral infection?
Death of T4+ cells by HIV
What are 2 examples of immunopathogenic disease?
-influenza A virus
Coxsackievirus- induced myocarditis
What are the site of viral entry? (7)
What kind of virus does the influenza A virus cause?
What kind of infections does enterovirus cause?
Describe the process of infection by the influenza A virus.
-virus infects cells of the respiratory tract
-destruction of respiratory epithelium
-altered cytokine expression leading to fever
Name 2 examples of cytokines that when expression is altered can lead to fever.
What can cause a cytokine storm?
Avian influenza virus (H5N1)
What is antigenic drift?
gradual evolution of viruses to generate antigenic variants
What is antigenic shift??
significant changes in virus antigenic structure
What plays a key role in generating new virus types through antigenic shift?
Name 5 examples of conditions and the enterovirus they are caused by.
-aseptic meningitis (many enteroviruses)
-myocarditis (coxsackie B viruses)
-pancreatitis (coxsackie B viurses)
-respiratory infection (many enteroviruses)
Give an example of a latent virus which has 2 types.
-Herpes simplex virus
-Type 1 =cold sores
-Type 2= genital lesions
Describe the process of infection by the latent herpes virus.
-primary infection of epithelial cells
-virus migrates to ganglia
-virus remains latent in nucleus= no virus replication
-stimuli such as sunlight reactivates virus
-virus migration to epithelial cells leading to virus replication
Give 2 examples of viruses which can induce tumours and what they can cause.
-Papillomaviruses- cervical carcinoma
-Retroviruses- lymphomas and leukaemias
What does HTLV-1 cause and how is it transmitted?
-variety of diseases including leukaemia (adult T cell lymphoma-leukaemia)
-transmission by blood and mother to child
What does HTLV-1 do?
modifies host cell gene expression using a transactivating protein (tax)