Third-generation tests

  • The first generation of ELISA tests for HIV antibodies were introduced in 1985.
  • The sensitivities and specificities of third-generation ELISAs are excellent.
  • However they are less good at detecting primary infection than fourth-generation tests, so their use is no longer recommended.

Most HIV antibody tests are in an ELISA or EIA format (enzyme-linked immunosorbent assay).

First-, second- and third-generation ELISAs screen for antibodies only. Because the test detects antibodies to HIV, as opposed to the virus itself, the ELISA is called an 'indirect test'.

Antibody-only ELISAs are no longer recommended for use in the UK, and should be replaced by fourth-generation ELISAs which also test for p24 antigen.

However an audit carried out in late 2009 showed that a number of laboratories had not shifted to fourth-generation tests.1

Related Links

References

  1. Moses S et al. UK CVN audit of HIV diagnostic service provision and practices 1st joint CVN, HPA, CHAIN and BHIVA meeting, London, 2010