Epidemiology of HIV in young people in England, Wales and Northern Ireland.

We describe the epidemiology of HIV among young people (15-24 years) in England, Wales and Northern Ireland (E, W&NI) between 1997 and 2001 inclusive. Rising rates of sexually transmitted infections (STIs) and 'risk' behaviours suggest that they are at increased risk of acquiring HIV. Data from three national surveillance systems are reviewed. Over the period, 1,624 young people were diagnosed with HIV (10% of all new diagnoses). In 1997 there were 254 new diagnoses, rising to 493 in 2001, a 1.9-fold increase. Of the total, 890 (55%) were heterosexually infected (81% female), 631 through sex between men, and the remainder via other routes. Where probable country of infection was reported (1,139), 618 (54%) were infected in Africa and 362 (32%) in the UK. In 1997, 675 young people accessed HIV-related services, rising to 975 in 2001: an increase of 1.4 fold. In 2001, for 34 of those accessing services the likely route of infection was perinatal. Between 1997 and 2001 inclusive, HIV prevalence among young heterosexual genitourinary medicine (GUM) clinic attendees was 0.17% (193/116,443), and for young homo/bisexual males, 3.4% (174/5,086). Sixty-five percent (104/159) of previously undiagnosed HIV-infected heterosexuals and 47% (51/108) of previously undiagnosed HIV-infected homo/bisexual males left the clinic unaware of their infection. In 2000 and 2001, overall prevalence was 0.11% (77/70,455) among young women giving birth. HIV diagnoses in young people have increased in recent years, while HIV prevalence among young people attending GUM clinics and giving birth has remained low. However, with dramatic increases in chlamydia rates among young women over the past decade, and the highest rates of gonorrhoea and concurrent partnerships among young people, concern about the potential for HIV transmission remains.