Injecting drugs in public places linked to a higher risk of HIV, hepatitis C and overdose, Scottish survey finds

Lack of safer drug consumption facility impeding efforts to control HIV outbreak among Glasgow drug users
Image: funnyangel/

People who inject drugs in public places in Scotland are much more likely to have HIV or hepatitis C and are at higher risk of overdose and skin and soft tissue infections caused by injecting, a survey of drug users has found. Scottish investigators say that their findings provide strong evidence in support of providing safer drug consumption facilities to prevent further drug-related harm.

Scotland’s largest city, Glasgow, has been affected by a major outbreak of HIV among people who inject drugs since 2014. The outbreak was detected in 2015 and by November 2018, 119 people had been diagnosed with HIV. HIV prevalence among the city’s injecting drug users increased from just over 1% in 2011 – among the lowest in the world – to 10.8% in 2018.

Scottish harm reduction experts and drug users have advocated the adoption of safer injecting facilities like those opened in Switzerland and Vancouver, Canada. As well as providing a space for supervised injecting with sterile injecting equipment to prevent overdose and blood-borne virus transmission, facilities can also offer health care for drug users, testing for HIV and hepatitis C and linkage to treatment.


adjusted odds ratio (AOR)

Comparing one group with another, expresses differences in the odds of something happening. An odds ratio above 1 means something is more likely to happen in the group of interest; an odds ratio below 1 means it is less likely to happen. Similar to ‘relative risk’. 

harm reduction

Harm reduction is a set of practical strategies and ideas aimed at reducing negative consequences associated with drug use (including safer use, managed use and abstinence). It is also a movement for social justice built on a belief in, and respect for, the rights of people who use drugs.


Studies aim to give information that will be applicable to a large group of people (e.g. adults with diagnosed HIV in the UK). Because it is impractical to conduct a study with such a large group, only a sub-group (a sample) takes part in a study. This isn’t a problem as long as the characteristics of the sample are similar to those of the wider group (e.g. in terms of age, gender, CD4 count and years since diagnosis).

blood-borne virus (BBV)

A virus transmitted through contact with infected blood. Hepatitis B, hepatitis C and HIV are BBVs. (Note that hepatitis B and HIV may also be transmitted through other body fluids).




A tentative explanation for an observation, phenomenon, or scientific problem. The purpose of a research study is to test whether the hypothesis is true or not.

Research in Glasgow suggests that around 500 people who inject drugs are regularly injecting in public places in Glasgow’s city centre but the United Kingdom government recently rejected a proposal to establish a drug consumption room in the city centre. Glasgow City Council and  Greater Glasgow and Clyde NHS continue to advocate for a safer drug consumption facility in the city centre.

Researchers from Glasgow Caledonian University, University of Glasgow and Scotland’s Health Protection Agency carried out a cross-sectional survey of people who inject drugs recruited through 139 harm reduction services in Scotland in 2017 and 2018. People were eligible to take part in the study if they had injected drugs in the previous six months.

Participants answered a structured questionnaire about drug-using behaviours and provided a dried blood spot sample for HIV and hepatitis C testing. Samples were tested for hepatitis C antibody and RNA to determine cases of chronic infection. 

The study recruited 1469 participants, 75% male with a mean age of 39 years. Fifteen per cent of the sample were recruited through services in Glasgow city centre, 25% in the Greater Glasgow area and 60% in other regions of Scotland.

Nearly a quarter of participants (23%) had injected cocaine and heroin in the previous six months and use of the two drugs was more frequently reported by people who also reported public injecting.

Although sharing of injecting equipment was infrequent – only one in ten reported sharing in the past six months – re-use of equipment was common. Fifty-eight per cent had re-used needles or syringes in the past six months.

Sixteen per cent of participants reported public injecting. Public injecting was much more frequent among drug users recruited through Glasgow City Centre sites where 47% of drug users reported recent injecting in a public place. Drug users in Glasgow were at least five time more likely to inject drugs in a public place than drug users in other regions of Scotland (adjusted odds ratio 5.45, 95% CI 3.48-8.54).

Public injecting was associated with homelessness (aOR 3.68, 95% CI2.61-5.19, p < 0.001), alcohol consumption > 14 units per week (aOR 2.42, 95% CI 1.69-3.44), injecting at least four times a day (aOR 3.16, 95% CI 1.93-5.18, p < 0.001) and cocaine injecting (aOR 1.46, 95% CI 1.00-2.13).

People who reported public injecting were more likely to have HIV (aOR 2.11, 95% CI 1.13-3.92, p = 0.019). HIV prevalence among public injectors was 7%. Public injectors also had higher likelihood of hepatitis C (aoR 1.49, 95% CI 1.01-2.19, p = 0.043) (47% prevalence).

"Although sharing of injecting equipment was infrequent, re-use was common."

Overdose was common among people who had injected in public. Thirty-seven per cent had overdosed in the previous year and public injectors had a higher risk of overdose (aOR 1.59, 95% CI 1.27-2.01, p < 0.001). Seventy per cent of all survey participants had received a prescription for naloxone, the drug that can prevent overdose death. People who injected drugs in public places also had a higher risk of skin and soft tissue infections (aOR 1.42, 95% CI 1.17-1.73, p < 0.001).

The investigators say that their findings “support the hypothesis that public injecting was a key risk factor in the HIV outbreak in Glasgow.” Forty per cent of people with HIV who use drugs in this sample reported public injecting and the prevalence of HIV among public injectors was 7%, compared to 1% in 2014. Although the study could not measure HIV incidence, the substantial increase in HIV prevalence between 2014 and 2017 indicates that HIV infection probably occurred recently in most people sampled in this study.

The high prevalence of hepatitis C also poses a risk to efforts to eliminate the virus in Scotland, say the investigators. Forty-seven per cent of people who reported public injecting had hepatitis C.

Similarly, the high prevalence of overdose in people injecting in public places challenges Scottish efforts to reduce drug-related deaths.

“Drug consumption rooms should be implemented as part of a comprehensive harm reduction approach, including opioid substitution therapy, needle exchange, safe injecting advice, naloxone and access to recovery services,” the investigators conclude.