Influenza immunisation coverage from 2015 to 2017: A national study of adult patients from Australian general practice

ObjectivesTo assess influenza immunisation rates and coverage in adult patients from Australian general practice and identify whether practice or patients’ characteristics are associated with vaccination uptake.DesignOpen cohort study.Setting550 Australian general practices included in the MedicineInsight database.ParticipantsPatients aged 18+ years who had at least one consultation during influenza season between 2015 and 2017. Two samples were considered: (1) ‘active’ patients (at least three consultations in any two consecutive years) and (2) ‘every year’ patients (at least one consultation per year).Main outcome measuresInfluenza vaccination rates per 1,000 consultations and coverage (% vaccinated among those who consulted) from 2015 to 2017.ResultsBetween 2015 and 2017 the influenza vaccine rate changed from 57.4 to 51.7 and 67.0 per 1,000 consultations, while correspondent values for coverage were 29.3%, 25.2% and 27.6% (in ‘active’ patients). Vaccine coverage was at least 30% higher in inner regional areas, among patients aged 65+ years or those with comorbidities. Similar associations were found among ‘every year’ patients, but average coverage across the three years was higher (41% vs 27%). Aboriginal and Torres Strait Islander people, either with or without comorbidity, showed a vaccine coverage 10–30% higher than non-Indigenous people for those aged less than 65 years (p-value for interaction < 0.001).ConclusionMedicineInsight data is a useful and low-cost method to monitor influenza immunisation coverage. Independent of the sample used, vaccination coverage among Indigenous people or patients with comorbidities could be improved. Targeted strategies for high-risk groups need to be developed.