Annual immunisation coverage report 2020 17 September 2021

Abstract

We analysed Australian Immunisation Register (AIR) data as at 31 March 2021 for children, adolescents and adults. This is the first time that adolescent and adult coverage data from the AIR have been included in our annual coverage report.
Children
‘Fully vaccinated’ coverage was 0.5–1.0 percentage points higher in 2020 than 2019 across the three standard age milestones, reaching 94.8% at 12 months, 92.1% at 24 months and 94.8% at 60 months. Rotavirus vaccine coverage (2 doses) increased from 91.9% in 2019 to 92.5% in 2020. ‘Fully vaccinated’ coverage in Aboriginal and Torres Strait Islander (hereafter respectfully referred to as Indigenous) children increased by 0.1–1.2 percentage points in 2020, reaching 93.1% at 12 months, 91.2% at 24 months and 97.0% at 60 months (2.2 percentage points higher than in children overall). Influenza vaccination coverage in children aged 6 months to < 5 years increased by 4.2 percentage points to 45.2% in 2020, and remained stable for Indigenous children at 43.6%. Longstanding issues with timeliness of vaccination in Indigenous children persist. We also examined timeliness of ‘fully vaccinated’ coverage at earlier age milestones (3 months after the due date of the last scheduled vaccine) of 9, 15, 21 and 51 months, by Indigenous status, socioeconomic status and remoteness of area of residence. Coverage in children living in the least advantaged residential area quintile was 1.9–2.5 percentage points lower than for those living in the most advantaged quintile at these earlier milestones, a 0.4–1.0 percentage points greater disparity than in 2019. Coverage at the earlier milestones in Indigenous children in remote areas was 2.6–7.8 percentage points lower than for Indigenous children in major cities and regional areas, with disparity at 21 months of age 0.5–0.8 percentage points higher in 2020 than in 2019, and 1.1–3.2 percentage points higher at 51 months. Importantly, although Indigenous children had slightly lower coverage for the second dose of measles-mumps-rubella-containing vaccine at 24 months (93.9% versus 94.0% overall), coverage among Indigenous children increased to 98.8% when measured at 60 months; coverage was also high overall at 96.8%, above the 95% target critical to measles control.
Adolescents
In 2020, the human papillomavirus (HPV) vaccination schedule was completed by 80.5% of females and 77.6% of males (75.0% and 68.0% for Indigenous) by 15 years of age, an increase of 0.6–0.7 of a percentage point on 2019 (2.6–3.4 percentage points for Indigenous). Additionally, 86.8% of adolescents (84.2% for Indigenous) had received the recommended booster dose of diphtheria-tetanus-acellular pertussis (dTpa) vaccine by 15 years, and 74.3% (68.1% for Indigenous) had received the recommended meningococcal ACWY vaccine dose by 17 years of age. However, the proportion of adolescents completing the 2-dose HPV vaccination schedule within a calendar year was 11.6 percentage points lower in 2020 than 2019; the number of dTpa doses in adolescents aged 11–15 years was 13.7 percentage points lower; and the number of meningococcal ACWY doses in adolescents aged 14–19 years was 4.1 percentage points lower, with these reductions likely due to COVID-19 pandemic-related disruption to school-based programs.
Adults
Recorded zoster vaccine coverage was relatively low in 70-year-old adults in 2020 at 30.4%, similar to 2019. Recorded influenza vaccination coverage in adults in 2020 increased with increasing age group, reaching 64% in the 65–69 year and 70% in the ≥ 75 year age group. Coverage also increased across all age groups between 2019 and 2020. These figures likely reflect some underreporting, with true coverage probably higher.
Conclusions
We found continuing improvements across a range of childhood immunisation indicators in Australia in 2020. While this predominantly reflects vaccinations due in 2019, due to the use of standard assessment time points 6–12 months after vaccines are due, other reports have indicated a lack of impact of the coronavirus disease of 2019 (COVID-19) pandemic on routine childhood vaccination in Australia. However, issues with timeliness of vaccination persist, particularly in Indigenous and socioeconomically disadvantaged children. Adolescent coverage was also relatively high, although with some evidence of pandemic impacts, so it will be important to monitor levels of adolescent catch-up vaccination. Adult coverage figures are likely underestimates due to underreporting of adult vaccinations to the AIR. Mandatory reporting of National Immunisation Program (NIP) vaccinations to the AIR, introduced in 2021, should improve reporting and enhance the AIR’s value for monitoring the successful delivery of the NIP.