Examining the impact of the first wave of COVID-19 and associated control measures on interventions to prevent blood-borne viruses among people who inject drugs in Scotland: an interrupted time series study

Background: COVID-19 has likely affected the delivery of interventions to prevent blood-borne viruses (BBVs) among people who inject drugs (PWID). We examined the impact of the first wave of COVID-19 in Scotland on: 1) needle and syringe provision (NSP), 2) opioid agonist therapy (OAT) and 3) BBV testing. Methods: An interrupted time series study design; 23rd March 2020 (date of the first 'lockdown') was chosen as the key date. Results: The number of HIV tests and HCV tests in drug services/prisons, and the number of needles/syringes (N/S) distributed decreased by 94% (RR=0.062, 95% CI 0.041-0.094, p < 0.001), 95% (RR=0.049, 95% CI 0.034-0.069, p < 0.001) and 18% (RR = 0.816, 95% CI 0.750-0.887, p < 0.001), respectively, immediately after lockdown. Post-lockdown, an increasing trend was observed relating to the number of N/S distributed (0.6%; RR = 1.006, 95% CI 1.001-1.012, p = 0.015), HIV tests (12.1%; RR = 1.121, 95% CI 1.092-1.152, p < 0.001) and HCV tests (13.2%; RR = 1.132, 95 CI 1.106-1.158, p < 0.001). Trends relating to the total amount of methadone prescribed remained stable, but a decreasing trend in the number of prescriptions (2.4%; RR = 0.976, 95% CI 0.959-0.993, p = 0.006) and an increasing trend in the quantity prescribed per prescription (2.8%; RR = 1.028, 95% CI 1.013-1.042, p < 0.001) was observed post-lockdown. Conclusions: COVID-19 impacted the delivery of BBV prevention services for PWID in Scotland. While there is evidence of service recovery; further effort is likely required to return some intervention coverage to pre-pandemic levels in the context of subsequent waves of COVID-19.