This statement from BASHH advises that new ‘fourth generation’ HIV tests will detect the majority of infected patients at four weeks post infection, which is much earlier than older tests. These tests look for both HIV antibodies and p24 antigen. I don’t know whether this test is being offered locally – so if in doubt – you may need to phone the lab and check.
When should you test?
- As soon as the patient attends after exposure – even if less than 4w as they may not reattend.
- Repeat 4w after exposure.
- If high risk exposure, repeat 8w after that exposure (only needed for high risk exposures as it is very likely to be positive at 4w if they have got HIV).