31st July 2023

Pathophysiology

The full scope of virus pathophysiology is beyond the remit of this section. Key principles to remember include:

• Viruses rely on a host to replicate and propagate
• Many of the clinical manifestations are the result of the immune response triggered by viral replication
• Host cell lysis will result in cell death locally and also contributes to the clinical illness

Viruses often have a specific action on a particular body system, owing to their individual molecular characteristics – this is known as tropism. Some viruses can cause disease in multiple tissue types, e.g. cytomegalovirus (CMV) in the immunosuppressed individual, which can cause CMV colitis, encephalitis, retinitis and hepatitis.