HIV transmission through injecting drug use on the increase in the UK

HIV transmission among injecting drug users is happening more often now than at the beginning of the decade, the Health Protection Agency says in a report issued this week. Infections in people who began injecting recently indicate recent transmissions, and prevalence in this group has risen considerably in recent years. However, overall HIV prevalence in drug users is stable.

The Health Protection Agency’s Unlinked Anonymous Prevalence Monitoring Programme’s Survey of Injecting Drug Users is an annual study of over 3,000 current and former injectors. The study is carried out at specialist services such as needle exchanges or methadone treatment programmes in England, Wales and Northern Ireland. Participants complete a questionnaire and provide an oral fluid sample for HIV testing.

Looking at the whole group of current and former injectors, 1.6% had HIV (51 of 3209 people), two-thirds of whom were aware of their infection. Prevalence was considerably higher in London (3.8%) than elsewhere.

Whereas survey results in 2006 and 2007 suggested that prevalence might be decreasing, this now appears not to be the case. Prevalence in 2008 was exactly the same as that recorded in 2005.

Turning now to HIV prevalence in those who began injecting in the past three years, it remained below 0.5% from 1991 to 2002. However, in the 2008 study it was 1.3% (5 of 391 people).

Another key indicator is prevalence among people who have injected in the past month. In London, which has the greatest concentration of infection, this has remained stable. However, elsewhere in England and Wales it increased from 0.25% in 2003 to 1.1% in 2008 (18 of 1604 people).

In addition, prevalence of hepatitis C remained high. Among those who began injecting in the past three years, 22% had hepatitis, half of whom were aware of their infection.

On a more optimistic note, the numbers reporting sharing equipment are lower than earlier in the decade. A total of 19% reported sharing needles or syringes, and 37% reported sharing spoons, mixing containers, filters or water.