Although it is difficult to estimate, figures suggest that the prevalence of opiate and crack cocaine injecting is in decline. The most recent figures (for 2010/11) suggest that an estimated 93,400 people inject opiates and/or crack in England (Hay et al. 2011). Prevalence seems to vary across regions.
In 2006, almost one-quarter (23%) of respondents to the 'Unlinked anonymous monitoring survey of people who inject drugs' (Public Health England 2013a) reported sharing needles and syringes in the previous 4 weeks. Almost half (45%) reported that they had shared filters, mixing containers and water within that time (Health Protection Agency et al. 2007).
Between 2001 and 2012, the number of people who injected drugs, and were in contact with specialist services that reported sharing needles and syringes, declined from 33% to 14%. The number who reported that they had shared filters, mixing containers and water declined to 34% (Public Health England (2013b).
The number of opiate-related (heroin or methadone) deaths has decreased over the years. However, over the past decade (2002 to 2010), they have accounted for around two-thirds of all drug-related deaths in the UK (Davies et al. 2012). Although not all opiate-related deaths occur in people who inject, it is thought that the vast majority do.
Sharing needles and syringes is a key route for transmitting blood-borne viruses among users. Sharing injecting equipment such as filters, mixing containers and water is also an important route of infection, particularly in the case of the hepatitis C virus. Data suggests that needle and syringe programmes are being accessed by increasing numbers of people who inject drugs across the UK. However, 'there remains a need to increase the amount of equipment distributed, with better targeting of this provision and education on appropriate needle and syringe cleaning techniques', according to Public Health England's hepatitis C in the UK 2013 report.
Hepatitis C is still the most widespread infectious disease affecting people who inject drugs, with 49% of people in England testing positive for antibodies in 2012 (Public Health England 2013b). In contrast, HIV prevalence has remained relatively low among injecting drug populations over the last decade (Health Protection Agency 2012). In addition, the prevalence of hepatitis B infection has declined (Health Protection Agency 2010).
Information is limited regarding the number of people using image- and performance- enhancing drugs. Anabolic steroid use is relatively widespread, with an estimated 59,000 people aged 16 to 59 years in England and Wales having used them in the past year (Drug misuse: findings from the 2012 to 2013 Crime Survey for England and Wales).
UK data suggest that the majority of people who use anabolic steroids inject them (Advisory Council on the Misuse of Drugs 2010), putting them at risk of bacterial and fungal infections and the transmission of blood-borne viruses.
The risk of blood-borne virus transmission among people who inject image- and performance- enhancing drugs may be lower than among groups who inject other drugs. However, a recent analysis estimated that the prevalence of HIV among men who inject these drugs is similar to that among people who inject psychoactive drugs. The study also showed that few of the men injecting performance- and image- enhancing drugs had ever had an HIV test. The authors urge targeted interventions for this group (Hope et al. 2013).
Users of image- and performance- enhancing drugs may represent a significant proportion of the people who use some needle and syringe programmes (Lenehan et al. 1996). There is evidence that people who inject steroids visit these services fewer times a year – collecting larger numbers of syringes in a single visit – than other users (McVeigh et al. 2003). Interviews with steroid injectors indicate that they often distribute injecting equipment among themselves (secondary distribution; McVeigh et al. 2007).
In addition to anabolic steroids, increasing numbers of new products are being injected. These include growth hormone and novel drugs (such as those that claim to stimulate secretion of growth hormone), IGF‑1 and analogues, and human chorionic gonadotrophin, which may enhance physical performance (Evans-Brown et al. 2012). They also include melanotans – products that claim to contain melanotan II (and to a lesser extent melanotan I). These are injected to look tanned and, in the case of melanotan II and bremelanotide, for their effect on sexual behaviour and function.
Although it is not known how many people use these new products, researchers have been alerted to their use in the general population through needle and syringe programmes seeking information after clients reported injecting these types of drugs (Evans-Brown et al. 2009).
It is not known how many people in the United Kingdom use drugs such as botulinum toxin or dermal fillers to reduce the appearance of wrinkles and lines but a number of factors suggest that there may considerable interest in these types of products among the general population (Evans-Brown et al. 2012).
Prevalence of drug injecting is higher among the 25 to 34 age group (17.9 per 1000) than the 15 to 24 age group (6.9 per 1000; Davies et al. 2010). It is not known how many people under 18 in England and Wales are involved.
Data from the National Treatment Agency suggest that in 2011/12, 156 young people aged 17 or under who were in drug treatment were currently injecting drugs, and 257 of this same group had experience of injecting. This is a decrease from 2010/11.
Data from the 'Unlinked anonymous monitoring survey of people who inject drugs' (Public Health England 2013a) suggest that in 2011, out of 2838 participants, 0.6% were under 18 (n=16) and 23% reported first injecting before age 18 (n=509). These numbers will represent a minority of young people who inject drugs, because UK evidence suggests that only 25% of this group are in treatment at any one time (Hickman 2004). It also suggests the proportion in treatment may be smaller for those under 18.
Evidence also suggests that among young people, vulnerable groups are more likely to inject drugs. This includes:
young offenders and those who are homeless or involved in sex work (Cusick et al. 2003)
those excluded from school (Melrose 2004)
young people with parents with drug or alcohol problems (Advisory Council on Misuse of Drugs 2003)
those who are, or have been, in care (Ward et al. 2003).
The government's 2010 drug strategy aims to reduce illicit and other harmful drug use. It also encourages an integrated approach to supporting people who want to recover from drug use.
Although the strategy places an emphasis on recovery, it specifically states that needle and syringe programmes, alongside treatment, can help: 'reduce the harms caused by dependence such as the spread of blood-borne viruses like HIV'.
Prevention of drug-related deaths and blood-borne viruses is also cited in the strategy as one of the eight 'best practice outcomes' that are key to successful delivery in a recovery-oriented system.