Despite the United Kingdom’s successful containment of HIV infection among people injecting drugs, progress towards lowering HIV prevalence and improving HIV care and treatment uptake within this population has stalled in the past ten years.
A recent article by researchers from the UK Health Security Agency published in the October issue of HIV Medicine tracks HIV prevalence, HIV diagnoses, risk and protective behaviours and quality of HIV care using data collected between 1981-2019 on adults who acquired HIV through injection drug use in England, Wales, and Northern Ireland. The researchers analysed two data sets. The first was national surveillance data of people diagnosed with HIV, collected through laboratories, clinicians, and NHS specialist HIV outpatient clinics, stored at the UK Health Security Agency. The second was the repeat Unlinked Anonymous Monitoring Survey, run annually since 1990 in England and Wales and since 2002 in Northern Ireland. This survey collects questionnaire data from people who have ever injected psychoactive drugs, recruited through specialised drug and alcohol services.
A changing, diverse population
Between 1981 and 2019, almost 5000 people who inject drugs in England, Wales, and Northern Ireland were diagnosed with HIV, representing 3.2% of all adults diagnosed with HIV. Annual diagnoses peaked in 1987 (234 diagnoses), falling to 78 in 2019. HIV prevalence in this population averaged out at 1%, with a high of 1.8% in the 1990s and a rate of 0.8% in 2019. HIV rates were higher among people injecting drugs born outside of England, Wales, and Northern Ireland and among those recruited for surveillance data in London.
This population has changed along lines of gender, age, and country of birth. Overall, since 1981, almost three-quarters of all people injecting drugs and diagnosed with HIV were White men aged 25-34 years, living in England. The proportion of male to female injection drug users diagnosed with HIV has increased from 2:1 in 1981-1989 to 4:1 in 2010-2019. Average age at HIV diagnosis rose from 27 in 1981-1989 to 37 in 2010-2019. This represents the ageing of a cohort of young adults who began injecting drugs during an ‘epidemic’ of injection drug use in the 1980s and 1990s. Finally, the proportion of HIV-diagnosed people injecting drugs in England, Wales and Northern Ireland who were born outside of the United Kingdom increased dramatically, from one in five in 1981-1989 to almost three in five in 2010-2019.
Overall, HIV treatment coverage was 70%, and viral suppression was 65%. Amongst those who did attend a clinic in 2019, the figures were 97% and 90% respectively. Being on treatment, and being virally suppressed, was more common among older HIV-positive injection drug users than among younger ones.
Successes, failures, and future risks
Late diagnosis is the leading predictor of poor health and early death among people living with HIV. Rates of late diagnosis among people injecting drugs – the group most prone to late diagnosis – remained consistently high over the four decades of data analysed, at 53%. However, slightly more men than women were diagnosed late, and the rate of late diagnosis rose with age, from 27% for those aged 15-24 years to 69% for those aged 50 and older.
Linkage to HIV care after diagnosis rose steadily, from 33% in the years 1981-1989 to 72% in 1990-1999, 96% in 2000-2009, and 98% in 2010-2019. However, one in five HIV-diagnosed people injecting drugs who were still alive in 2019 did not attend HIV care post diagnosis, and approximately one-third had last attended pre-2019.
While HIV testing rates among people injecting drugs improved over time (from approximately half in 1990 to approximately four in five in 2019), there has been no progress over the past decade. In 2019, 20% of those currently injecting drugs had never been tested for HIV despite having engaged with health care services, including services focusing on drugs and alcohol, and despite HIV testing guidelines recommending annual testing for people injecting drugs, including at drug services.
This recent lack of progress was also evident in the area of risk and protective behaviours. On the one hand, awareness of HIV almost doubled (from 56% to 100%) between 2005 and 2019. On the other hand, rates of sharing syringes, needles, and other drug equipment, which peaked in 2002, have remained stable at 37% since 2012.
The authors list several successes in containing HIV infection among people injecting drugs in England, Wales, and Northern Ireland. Rates of HIV infection among people injecting drugs remain ‘relatively contained’ when compared with other countries: for example, HIV prevalence among people injecting drugs is 60% in Estonia and 48% in Spain. The United Kingdom’s containment of HIV infection among people injecting drugs is likely due to early introduction of harm reduction, including needle and syringe programmes and opioid substitution therapy. Moreover, providing HIV testing outside of traditional settings has made HIV surveillance more attuned to underserved groups and improved access to HIV services.
But the authors also contrast these with the lack of progress towards risk reduction, HIV testing, early diagnosis and HIV care uptake over the past decade and call for improved HIV prevention measures and programmes in England, Wales, and Northern Ireland. They argue that recent sporadic outbreaks of HIV among people injecting drugs within the United Kingdom, an ongoing outbreak of HIV among people injecting drugs in and around Glasgow in Scotland, an increase in new HIV diagnoses among people injecting drugs who were born outside the United Kingdom, and a 28% increase in the injection of crack cocaine between 2010-2019, all call for continued surveillance of this population’s infection rate and risk behaviours. The increase in cases of HIV among people injecting drugs, they write, is further increased by significant cuts to funding for drug treatment in recent years and the COVID-19 pandemic’s restriction of access to harm reduction services.
Croxford S et al. Epidemiology of HIV infection and associated behaviours among people who inject drugs in England, Wales, and Northern Ireland: Nearly 40 years on. HIV Medicine 23: 978-989, 2022 (open access).
Full image credit: Two syringes, powder and spoon on old wooden background. Image by Marco Verch. Available at https://foto.wuestenigel.com/two-syringes-powder-and-spoon-on-old-wooden-background/ under a Creative Commons licence CC BY 2.0.