Glossary

haematology – study (-ology) of blood (haema-)

mean (average) – where all the results are added together, and then divided by the number of results to find the (mean) average. See median.

What is an average.

surrogate marker – A surrogate marker is when something that is easy to measure is used as a marker for something that is difficult to measure directly.

The CD4 count doesn’t directly measure HIV. But it is a good surrogate (or indirect) marker for how HIV has damaged your immune system. It is closely linked to the risk of HIV-related complications.

Viral load in blood is a good surrogate marker for levels of HIV in your body overall including in other body sites.

severity – a measure of how bad something is.

latent – not active at present, resting. Latently infected CD4 cells are CD4 cells that are infected with HIV but which are resting. HIV drugs do not work on resting cells.