Recent Infection Testing Algorithm (RITA)/HIV Incidence

HIV poses a unique challenge to the public health monitoring of communicable diseases as a result of the extended period between infection and the onset of symptoms, which is typically between eight and eleven years. Current tests for HIV are unable to distinguish recently acquired infections (incident infections) from long standing infections. This means that newly diagnosed infections that are reported to the HIV and AIDS Reporting Section (HARS) at the HPA may have been acquired over a wide time interval. With the number of newly diagnosed infections continuing to increase, we have only limited ability to assess whether this increase is as a result of the success in promoting HIV testing, or a failure to reduce HIV transmission.

Controlling the spread of HIV within the UK population requires that we have a clear idea of who is at greatest risk of acquiring HIV, and tailor health promotion initiatives to meet their needs. We are therefore in the initial phases of extending the current national monitoring of HIV to include testing for HIV incidence as an indicator of HIV transmission.