Theme: Epidemiology & Public Health Research Year: 2022
Background: Syringes with attached needles (termed fixed low dead space syringes [LDSS]) retain
less blood following injection than traditional syringes with detachable needles (termed high dead
space syringes [HDSS]). The World Health Organization recommends LDSS provision for reducing
blood borne virus transmission among people who inject drugs (PWID), however, empirical evidence
supporting this recommendation is lacking.
Methods: The UK Unlinked Anonymous Monitoring cross-sectional bio-behavioural survey surveys
PWID attending harm reduction services. The 2016, 2018, and 2019 surveys tested for hepatitis C
virus (HCV) RNA amongst HCV antibody-negative (marker of recent HCV infection) PWID and
included questions on the percentage of syringes used in the past month with attached needles
(fixed LDSS) or detachable needles (HDSS or detachable LDSS). Using multivariable logistic
regression, we investigated whether always using fixed LDSS (versus any use of syringes with
detachable needles) was associated with recent HCV infection amongst antibody-negative PWID that
reported injecting last month.
Results: Of 1,429 included participants, 64.1% always used fixed LDSS, 25.2% always used syringes
with detachable needles, and 10.7% used both. There were 33 recent HCV infections. Compared to
any use of syringes with detachable needles, always using fixed LDSS was associated with lower
likelihood of recent HCV infection in unadjusted (odds ratio [OR] 0.32, 95% confidence interval 0.14-
0.74) and adjusted analyses (adjusted OR 0.24, 0.08-0.67).
Conclusion: Exclusive use of fixed LDSS was associated with a 76% reduced risk of recent HCV
acquisition amongst PWID. This suggests that the use of LDSS could be highly protective against HCV,
suggesting that strategies to eliminate HCV (and HIV) should expand the use of LDSS.
Disclosure of interest: No pharmaceutical grants were received in the development of this study.
This work was supported by the National Institute of Health Research Health Protection Research
Unit in Evaluation and Behavioural Science.