Uptake, barriers and correlates of influenza vaccination among people who inject drugs in Australia

•Vaccine uptake among people who inject drugs was lower than the general population.•Barriers to vaccination were predominantly related to lack of perceived vaccine utility.•Those reporting recent opioid agonist therapy were more likely to be vaccinated. Comorbid chronic health conditions place people who inject drugs (PWID) at risk of severe health outcomes after influenza infection. However, little is known about the uptake, barriers and correlates of influenza vaccination among PWID. During structured surveys, 872 PWID reported whether they had received an influenza vaccination during the last year (disaggregated as pre- or post-March 2020 to ascertain current season vaccine uptake), and if not, the barriers to vaccination. Logistic regression was used to examine demographic, drug use, health and service engagement correlates of vaccine uptake. Thirty-nine percent of participants reported past-year influenza vaccination, with one-quarter (24 %) vaccinated in the current season. The main barriers to vaccination were motivation-based, with few citing issues relating to affordability, supply or perceived stigma. Opioid agonist therapy in the past six months was significantly associated with vaccination. Influenza vaccine uptake was lower among PWID than the Australian general population. Provision of the vaccine at services commonly accessed by PWID may increase uptake.