Abstract

Objectives: To determine whether the increase in HIV diagnoses since 1997 among men who have sex with men (MSM) in the UK reflects a rise in HIV incidence or an increase in HIV testing.

Methods: Estimates of HIV incidence were derived using data from UK HIV surveillance systems (HIV diagnoses; CD4 surveillance; unlinked anonymous surveys) for 1997-2003. Data on HIV testing were provided by KC60 statutory returns and unlinked anonymous surveys in sentinel GUM clinics.

Results HIV diagnoses among MSM in the UK rose by 43% between 1997 and 2003 (1,382, 1,979), with variation by age and geographic location. There was no increase in the number of HIV diagnoses among MSM <35 years in London, but in all other groups it increased. Indirect estimates suggest there may have been an increase in HIV incidence among MSM <35 years in London and among MSM (all ages) elsewhere in England, Wales and Northern Ireland (E,W&NI) but not in Scotland. However, direct point estimates only indicated an increase in HIV incidence among older MSM in London; this change was not statistically significant. Throughout the UK, uptake of HIV testing increased significantly among MSM attending GUM clinics between 1997-2003, including 'at-risk' MSM (p<0.001).

Conclusions: In London, HIV incidence may have increased since 1997 among older MSM, but not among younger MSM for whom the number of HIV diagnoses did not rise between 1997-2003. HIV incidence appeared to remain constant among MSM in Scotland, while elsewhere in E,W&NI, changes in incidence were difficult to discern. Throughout the UK, there has been a substantial increase in HIV testing among MSM since 1997.