All patients attending a genitourinary medicine (GUM) clinic should be offered an HIV test, according to the National Strategy for Sexual Health and HIV, as part of the initial screening for sexually transmitted infections.¹ This does not mean that testing is restricted to new patients only and all re-presenting HIV negative patients should be offered and encouraged to have serological testing for HIV and syphilis following possible re-exposure.

Screening of symptomatic and asymptomatic patients attending GUM clinics for HIV is indicated for the following reasons:

• The benefits of early self knowledge of HIV infection in controlling the spread of HIV infection are now recognised.²

• There is also enough evidence through cohort studies which show that many people will reduce sexual and needle sharing risk behaviour after a diagnosis of HIV infection^{3,4,5,6,7,8,9,10} and, similarly, those who are unaware of their HIV status do not change their high risk behaviours.^6,11–13

• Highly active antiretroviral treatment (HAART) is an important contributor in reducing transmission as a result of the reduction in HIV burden and therefore infectivity in those individuals who are diagnosed early and treated.¹⁴

• There is also consensus that it is best to start HAART before the onset of severe immunosuppression.¹⁵

Screening of asymptomatic at-risk groups is most effective if it is coupled with a personalised prevention counselling service. The screening service should provide information regarding the transmission, prevention, and the meaning of HIV test results.¹⁶ This information should form part of a leaflet that everybody should receive. Additional information should be offered to those refusing a test as lack of perceived risk has been found to be the main reason for test refusal.¹⁷ Confidentiality of patients must be ensured and informed consent must be obtained …