The annual report of the UK Health Protection Agency (17th June, 2011) offers a concise and accessible statistical overview of recent trends in STIs (not including HIV/AIDS), as well as details of the UK Chlamydia screening programme and the recent epidemic of lymphogranuloma venereum (LGV).
The overall picture suggests a slight decline (1%) in STIs in 2010, and – for the first time since records began – no rise in chlamydia diagnosis (despite the continued scale-up of testing). The overall decline conceals a continued rise in gonorrhoea (3%) and herpes (8%) diagnosis, partly attributable to more sensitive diagnostic tests.
Those aged under 25 account for 63% of chlamydia diagnosed, 54% of genital warts, 47% of gonorrhoea, 41% of genital herpes. Trends since 2008 differ somewhat according to sex. Among women the 15-24 year olds are very considerably the most severely affected group, and have seen a continued slight decline in gonorrhoea and genital warts diagnosis. Among men cases seems less unevenly spread overall, but with 20-24 years old the most affected. These have seen a continued rise in gonorrhoea diagnosis.
Men who have sex with men (MSM) are the other key population. These account for 64% of syphilis and 40% of gonorrhoea. Here there is less cause for cheer. Gonorrhoea diagnosis has continued to rise (up by a third in the past year), while Syphilis continues on its upward trajectory. Given the high risk of exposure to HIV/AIDS in the MSM population (a dimension of the STIs picture that is absent from this report, which fails to make the link between STI and HIV), these figures are particularly worrying.
The report concludes with statistics for the epidemic of lymphogranuloma venereum (LGV). This began in the late 2004 and has intensified considerably, with a third of the total number of 1,665 cases having been diagnosed since 2010 – largely among white HIV positive MSM.

HPA, Health Protection Report, HIV/Sexually Transmitted Infections (STIs), vol. 5, no.24, 17th June 2011

http://www.hpa.org.uk/hpr/infections/hiv_sti.htm