Virus Pathogenesis Flashcards
What are a viruses 3 pathogenic mechanisms?
Cell destruction
Virus induced changes to cellular gene expression
Immunopathogenic diease
Give examples of sites of viral entry into the body
Respiratory tract Alimentary tract Urinogenital tract Skin Capillary Conjuctiva
What is an acute virus infection?
One that comes then goes away
What is a latent virus infection?
One that comes and stays latent able to strike again symptoms come in intervals
What is a chronic virus infection?
One that comes and never goes - symptoms are ongoing
Give an example of an acute viral infection?
Influenza virus - respiratory infection
Enterovirus - enteric and neurological infections
How far do acute virus infections spread in the body?
Not very far
Localised to specific site on the body
What cells does the virus influenza infect?
Cells of the respiratory
What is a cytokine storm?
When the immune system has such an over reactive response to the pathogen that it releases loads of cytokines
Is destruction of respiratory epithelium a primary or secondary bacterial infection?
Secondary
Influenza changes strain slightly every year what is this known as?
Antigenic variation
If there is a significant change in the viruses antigenic structure what is this known as?
Antigenic shift
What is a enterovirus?
Type of virus
What virus causes poliomyelitis/
Poliovirus
What virus causes pancreatitis and myocarditis?
Coxsackie B virus
What virus causes respiratory infections?
Many viruses
Give an example of a latent virus/
Herpes simplex virus
What does type 1 herpes virus cause?
Cold sores
What does type 2 herpes virus cause?
Genital lesions
In the period between infections in latent viruses are symptoms experienced?
No
Where does the latent herpes virus remain?
In the nucleus of the ganglia
Broadly what reactivates the latent virus?
Stimulus
After the reactivation of the latent herpes virus where does it head to?
Epithelial cells
What can the papilloma virus lead to?
Cervical carcinoma
What is a tumour caused by a virus known as?
Virus-induced tumour
What tumours can a retrovirus induce?
Lymphomas and Leukaemias
Does a retrovirus contain RNA or DNA?
RNA
What happens to the RNA in a retrovirus?
It enters and integrates into the hosts cell DNA
When a viruses DNA enters the hosts cells genome what does this cause?
Changes in cellular gene expression
What enzyme converts the RNA into DNA in the hosts genome?
Reverse transcriptase
Can Retroviruses induce tumours?
Yes
Retrovirus induced tumours
