antigen – a protein found on the surface of a virus or bacteria. It is recognised by the immune system which then generates antibodies.
Glossary
Selected words and phrases
sensitivity – when referring to the accuracy of a test result, sensitivity refers to the proportion of people with an illness or disease who have a positive test result.
If a test has low sensitivity, then false-negative results are the concern – where people have a condition but it is missed.
If a test has high sensitivity, then people are accurately diagnosed – and only a few people are missed.
For a serious condition, high sensitivity is essential to be able to identify people early.
See specificity.
sensitivity – when referring to the activity of a drug, sensitive means that a drug still works. As resistance develops a drug becomes less sensitive.
A complete loss of sensitivity implies that a drug is no longer working.
It also means that your partner may benefit from counselling.
HAART – a common term for HIV combination therapy, an acronym for Highly Active AntiRetroviral Treatment.
clinical failure – when you develop new symptoms and illnesses even though you are on treatment. See virological failure.
codon – the word for the junction on genetic material (DNA or RNA) occupied by three nucleotides (or bases) to form an amino acid. In HIV it is most used when refering to drug resistance. There is an amino acid at each codon and the codons are numbered (starting from 1) for each section of the HIV gene. For example the mutation M184V in RT refers to a mutation change at codon 184 in the reverse transcriptase gene.