viral load

viral load – the amount of virus in a sample of blood or other fluid. With HIV this is commonly the amount of HIV in a millilitre (mL) of blood. See viral load test.

viral tropism

viral tropism see tropism.


virion – the name for a virus when it is not inside a cell, for example when new viral material leaves a CD4 cell and is floating in blood or plasma

viral rebound

viral rebound – when your viral load has been undetectable (under 50 copies/mL) and then becomes detectable. Sometimes viral rebound can be a lab error, sometimes a small temporary blip, and sometimes a real rebound that shows your virus may …

viral load test

viral load test – a test that detects whether a virus is present (qualatitive) or that measures the amount of virus (quantitative). This is usually in a sample of blood, but a viral load test can also be used to …

virological failure

virological failure – the term for when viral load levels never reach undetectable, or if they rebound to higher levels after previously being undetectable. See clinical failure.


virology – the study of viruses.


virus – an infectious organism that can only reproduce inside the cell of another plant or animal.


varices – extended or swollen veins in the liver that can burst. They can be a complication of cirrhosis.