Annual immunisation coverage report 2021.

Introduction: We analysed Australian Immunisation Register (AIR) data as at 3 April 2022 for children, adolescents and adults for the calendar year 2021, with data on trends from previous years also presented. Children: 'Fully vaccinated' coverage in Australian children in 2021 was 0.6-0.8 of a percentage point lower than in 2020 at the 12-month (94.2%) and 60-month (94.0%) age assessment milestones, but stable at the 24-month milestone (92.1%). Due to the lag time involved in assessment at milestone ages, 'fully vaccinated' coverage figures for 2020 and 2021 predominantly reflect vaccinations due in 2019 and 2020, respectively, and hence show a small impact on childhood coverage in the first year of the coronavirus disease 2019 (COVID-19) pandemic. 'Fully vaccinated' coverage in Aboriginal and Torres Strait Islander (hereafter respectfully referred to as Indigenous) children was 0.7-1.5 percentage points lower in 2021 than 2020 at the 12-month (91.6%), 24-month (90.1%) and 60-month (96.3%) milestones, although 2.3 percentage points higher than children overall at 60 months. Influenza vaccination coverage in children aged 6-59 months was approximately 20 percentage points lower in 2021 than 2020, both for children overall (26.5%) and for Indigenous children (22.5%). 'On time' vaccination (within 30 days of the recommended age) was up to two percentage points lower in 2021 than 2020 for vaccines due at 4 and 6 months of age, suggesting possible pandemic impacts, but was similar or higher for vaccines due at 12 months of age. While on-time vaccination in Indigenous children has improved progressively since 2012, it remained 6-13 percentage points lower than in children overall in 2021. 'Fully vaccinated' coverage at the earlier milestones (3 months after due date of last scheduled vaccine) of 9, 15, 21 and 51 months was 1.5-2.8 percentage points lower for children living in the least advantaged residential area quintile than the most advantaged, a similar disparity as in 2020. Coverage at the earlier milestones was 2.3-10.0 percentage points lower for Indigenous children living in remote areas than in major cities and regional areas, with disparity at 21 months of age 2.1-2.2 percentage points higher in 2021 than in 2020, and 1.2-2.1 percentage points higher at 51 months. Adolescents: In 2021, a total of 80.3% of girls and 77.2% of boys (and 73.3% and 66.2% of Indigenous girls and boys) had completed the human papillomavirus (HPV) vaccination schedule by 15 years of age, 0.2-0.4 of a percentage point lower than 2020 (1.7-1.8 percentage points for Indigenous), reflecting vaccinations due in school programs prior to the pandemic with possible pandemic impact on catch-up vaccination. However, the proportion of adolescents completing the two-dose HPV vaccination schedule within a calendar year was 15.3 percentage points lower in 2021 than 2020 and 26.9 percentage points lower than in 2019, likely due to pandemic-related disruption to school-based programs. Additionally, 87.3% of adolescents (83.8% for Indigenous) had received the recommended booster dose of diphtheria-tetanus-acellular pertussis (dTpa) vaccine by 15 years, and 76.1% (66.7% for Indigenous) the recommended meningococcal ACWY vaccine dose by 17 years of age. Adults: Zoster vaccine coverage in 2021 remained relatively low, at just over 30%, in adults aged 70 years, but increased to 47% in those aged 71-79 years, reflecting ongoing catch-up vaccination. Coverage of 13vPCV was low in 2021, reaching 17.2% in adults aged 70 years and 20.1% in those aged 71-79 years. Influenza vaccination coverage in adults in 2021 was progressively higher with increasing age, reaching 62.1% in the 65-74 years age group (64.6% in Indigenous) and 68.5% in the 75+ years age group (67.7% in Indigenous). Influenza vaccine coverage for other National Immunisation Program (NIP)-eligible Indigenous adult age groups was only 22.0% for those aged 20-49 years, and 43.5% for those aged 50-64 years. By the end of 2021, a total of 91.6% of people in Australia aged 16+ years had received a second dose of a COVID-19 vaccine (71.8% for Indigenous), with over 99% of those aged 70+ years having received a second dose. Conclusions: Vaccination coverage in children and adolescents remained relatively high in 2021, although with some evidence of COVID-19 pandemic impacts, particularly on receipt of two doses of HPV vaccine within the same calendar year. It will be important to ensure catch-up vaccination in children and adolescents occurs. A strengthened focus on adult vaccination is needed, as coverage remained suboptimal in 2021. The impact of mandatory reporting of all NIP vaccinations from mid-2021, on completeness of AIR data, has not yet been formally evaluated.

Disseminated varicella zoster virus infection following live attenuated herpes zoster vaccine: descriptive analysis of reports to Australia's spontaneous vaccine pharmacovigilance system, 2016-2020.

OBJECTIVES: To examine the reported incidence and features of disseminated varicella zoster virus (VZV) infection following live attenuated herpes zoster vaccine live (ZVL: Zostavax, Merck) in immunocompromised people in Australia. DESIGN AND SETTING: ZVL was funded in 2016 in Australia for people aged 70 years, with a catch-up programme for those 71-79 years. From 2016 to 2020, three deaths due to disseminated vaccine-strain VZV infection occurred following inadvertent ZVL administration in individuals with varying levels of immunocompromise. This descriptive study examined 4 years of national surveillance data reported to the Therapeutic Goods Administration's Adverse Event Monitoring System (AEMS). Denominator data for rates were from doses recorded in the Australian Immunisation Register. PARTICIPANTS: Individuals vaccinated between 1 November 2016 and 31 December 2020 who experienced adverse event(s) following immunisation (AEFI) after ZVL recorded in the AEMS. PRIMARY AND SECONDARY OUTCOME MEASURES: Rates and outcomes of confirmed (Oka strain positive) or probable disseminated VZV infection, and inadvertent administration of ZVL in immunocompromised individuals. RESULTS: 854 AEFI were reported from 1 089 966 doses of ZVL administered (78.4 per 100 000 doses). Of those, 14 were classified as confirmed (n=6, 0.55 per 100 000) or probable (n=8) disseminated VZV infection. The confirmed cases were all hospitalised, and most (5/6) were immunocompromised; three cases died. Thirty-seven individuals were reported as vaccinated despite a contraindication due to immunocompromise (3.4 per 100 000), with 12/37 (32%) hospitalised. CONCLUSIONS: Disseminated VZV is potentially life-threatening and occurs mostly in those with severe immunocompromise. Inadvertent administration of ZVL to immunocompromised individuals has occurred despite initial provider guidance and education. Multiple additional strategies to assist providers to identify contraindications have been implemented to prevent adverse outcomes.

Annual immunisation coverage report 2020.

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.

How accurately does the Australian Immunisation Register identify children overdue for vaccine doses? A national cross-sectional study.

Abstract: The accuracy of data recorded in the Australian Immunisation Register (AIR) is important for assessment of population-level vaccine coverage but has not been assessed nationally since 2001. We undertook a cross-sectional study in five states in 2017 using standard criteria to validate AIR records classified as three months overdue for any vaccine at 12, 24 and 48 months. Of 2,000 records selected for audit, 905 were assessable, of which 124 (14%) were misclassified as overdue (errors). Among 563 general practice (GP) records, 91 (16.1%) were errors. Compared with Victoria (1/99; 1%), errors were significantly higher in Western Australia (11/106; 10.4%), Queensland (13/104; 12.5%), South Australia (23/110; 20.9%) and New South Wales (43/144; 29.9%); p < 0.01 for all. Among 165 council and community health centre providers, the overall error rate (17; 10.3%) was non-significantly lower than for GP providers, with an odds ratio (OR) of 0.6 and a 95% confidence interval (95% CI) of 0.3-1.1, and did not differ between states. Records were transmitted to the AIR by paper-based methods in 13 cases, with significantly higher error rates (7/13; 54%) than for practice management software (77/630; 12.2%); OR 9.8 (95% CI 2.8-36.4) or the AIR secure site (23/87; 26.4%); OR 2.6 (95% CI 1.4-4.5). Accuracy is increasingly important, with mandatory reporting to the AIR for all National Immunisation Program vaccines from July 2021, and best achieved by uniform use of practice management software.

HPV vaccination coverage: slightly improved two-dose schedule completion estimates and historical estimates lower on AIR than HPV Register.

OBJECTIVE: To compare Australian Immunisation Register (AIR) human papillomavirus (HPV) vaccination coverage against historical data from the former National HPV Vaccination Program Register and estimate two-dose vaccination coverage. METHODS: Cross-sectional analysis of registry data for adolescent birth cohorts (1998-2007). Denominator populations were Medicare enrolments (AIR) and ABS estimated resident populations (HPV register). RESULTS: For adolescents aged <17 years, AIR coverage estimates were several percentage points lower than HPV register estimates due to a larger Medicare enrolment denominator. Completed course coverage (two or three valid doses) for 15-year-old females in 2020 was 81.5% and for males 78.6%, higher than completed course coverage in 15-year-olds in 2019 (79.7 and 76.8% respectively). First dose coverage was similar for Indigenous adolescents but course completion was lower, although improving over time. Course completion was slightly lower (3.5-5.7%) in areas of lowest socioeconomic status and greatest remoteness. CONCLUSIONS: Coverage is slightly lower using AIR than HPV register estimates. Moving from three to two doses has slightly improved completion, likely due to the wider dose spacing, but equity gaps remain. IMPLICATIONS FOR PUBLIC HEALTH: An ongoing focus on equity in vaccine delivery is needed. Systems, reminders and catch-up opportunities to ensure course completion remain important.

Immunisation Coverage Annual Report 2018.

Abstract: Australian Immunisation Register data have been analysed for children aged < 5 years, focusing on changes in coverage at key milestone ages (12, 24 and 60 months) between 2017 and 2018, while also documenting longer term trends. Fully vaccinated coverage increased at the 12- and 60-months milestones to 93.9% and 94.0%, respectively, but, in the context of additional antigens required, decreased to 90.1% at 24 months. Following the move to a two-dose rotavirus vaccine schedule across Australia from mid-2017, rotavirus vaccine coverage increased from 86.8% to 90.9%. In 2018, most jurisdictions funded influenza vaccine for non-Indigenous children aged 6 months to < 5 years; the National Immunisation Program has funded influenza vaccine for Aboriginal and Torres Strait Islander children and medically at-risk children since 2015 and 2010, respectively. Recorded influenza vaccine coverage in Aboriginal and Torres Strait Islander children doubled from 14.9% to 31.4%, and increased fivefold in non-Indigenous children from 5.0% to 25.9% in 2018. The timeliness of fully vaccinated coverage was also examined at earlier milestones (3 months after due date of last scheduled vaccine) of 9, 15, 21 and 51 months, by area of residence. For all children, coverage among those living in the least advantaged residential area quintile was 3-4% lower than that for those in the most advantaged quintile at the 9-, 15- and 21-month milestones. Importantly, although Aboriginal and Torres Strait Islander children had lower coverage for the second dose of measles-mumps-rubella vaccine at 24 months (91.8% versus 93.1% for non-Indigenous), coverage increased to 98.5% at 60 months; coverage was also high in non-Indigenous children at 96.2%, above the 95% target critical to measles control. These data demonstrate continuing improvements in immunisation coverage and suggest potential new coverage targets for earlier protection in the first two years of life.

Immunisation Coverage Annual Report 2019.

Abstract: Australian Immunisation Register data have been analysed for children aged < 5 years, focusing on changes in vaccination coverage at standard age milestones (12, 24 and 60 months) between 2018 and 2019. 'Fully vaccinated' coverage in 2019 increased by 0.1-0.4% at the three age milestones to 94.3% at 12 months, 90.2% at 24 months (in the context of additional antigens required at 24 months) and 94.2% at 60 months. Rotavirus vaccine coverage (2 doses) increased from 90.9% in 2018 to 91.9% in 2019. 'Fully vaccinated' coverage in Aboriginal and Torres Strait Islander (hereafter respectfully referred to as Indigenous) children increased by 0.5-1.1% in 2019, reaching 92.9% at 12 months, 88.9% at 24 months and 96.9% at the 60 months (2.7 percentage points higher than in children overall). Recorded influenza vaccination coverage in children aged 6 months to < 5 years increased by 11.4 percentage points to 42.7% in Indigenous children in 2019, and by 15.6 percentage points to 41.8% in children overall. Longstanding issues with timeliness of vaccination in Indigenous children persisted, although the disparity between Indigenous and non-Indigenous children in on-time coverage (within 30 days of due date), for vaccines due at 4 months of age, decreased from 10.4-10.7 to 9.6-9.8 percentage points between 2018 and 2019. The timeliness of 'fully vaccinated' coverage was also examined at earlier age milestones (3 months after due date of 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 2.6-2.7% lower than that for those living in the most-advantaged quintile at the 9-, 15- and 21-month milestones, although these disparities were 0.5-1.5 percentage points lower than in 2018. Coverage at the earlier milestones in Indigenous children in remote areas was 1.5-6.7% percentage points lower than that for Indigenous children in major cities and regional areas, although there were some improvements since 2018. Importantly, although Indigenous children had lower coverage for the second dose of measles-mumps-rubella vaccine at 24 months (92.7% versus 93.3% overall), coverage increased to 98.8% at 60 months; coverage was also high overall at 96.4%, above the 95% target critical to measles control. In conclusion, this report demonstrates continuing improvements across a range of immunisation indicators in Australia in 2019. However, some issues with timeliness persist, particularly in Indigenous and socioeconomically disadvantaged children. New coverage targets for earlier protection in the first 2 years of life may be indicated, along with a review of current 'fully vaccinated' assessment algorithms, particularly at the 60-month age milestone.

"No jab, no pay": catch-up vaccination activity during its first two years.

OBJECTIVES: To assess catch-up vaccination of older children and adolescents during the first two years of the "No jab, no pay" policy linking eligibility for federal family assistance payments with childhood vaccination status. DESIGN, SETTING, PARTICIPANTS: Cross-sectional analysis of Australian Immunisation Register data on catch-up vaccination of children aged 5 to less than 7 years before (January 2013 - December 2014; baseline) and during the first two years of "No jab, no pay" (December 2015 - December 2017), and of children aged 7 to less than 10 years and young people aged 10 to less than 20 years ("No jab, no pay" period only). MAIN OUTCOMES: Catch-up vaccination rates for measles-mumps-rubella vaccine second dose (MMR2), by age group, Indigenous status, and socio-economic status; catch-up vaccination of children aged 5 to less than 7 years (third dose of diphtheria-tetanus-pertussis vaccine [DTPa3], MMR1), before and after introduction of "No jab, no pay". RESULTS: The proportion of incompletely vaccinated children aged 5 to less than 7 years who received catch-up DTPa3 was higher under "No jab, no pay" than during the baseline period (15.5% v 9.4%). Of 407 332 incompletely vaccinated people aged 10 to less than 20 years, 71 502 (17.6%) received catch-up MMR2 during the first two years of "No jab, no pay", increasing overall coverage for this age group from 86.6% to 89.0%. MMR2 catch-up activity in this age group was greater in the lowest socio-economic status areas than in the highest status areas (29.1% v 7.6%), and also for Indigenous than for non-Indigenous Australians (35.8% v 17.1%). MMR2 catch-up activity in 2016 and 2017 peaked mid-year. CONCLUSIONS: Linking family assistance payments with childhood vaccination status and associated program improvements were followed by substantial catch-up vaccination activity, particularly in young people from families of lower socio-economic status.

Infant, maternal and demographic predictors of delayed vaccination: A population-based cohort study.

BACKGROUND: Receiving vaccines at or close to their due date (vaccination timeliness) is a now key measure of program performance. However, studies comprehensively examining predictors of delayed infant vaccination are lacking. We aimed to identify predictors of short and longer-term delays in diphtheria-tetanus-pertussis (DTP) vaccination by dose number and ethnicity. METHODS: Perinatal, notification, death and immunisation databases were linked for 1.3 million births in 2000-11 from two Australian states (Western Australia and New South Wales), with follow-up data until 2013. Ordinal logistic regression was used to estimate adjusted relative risks (RR) by degree of delay. Separate models were constructed for each vaccine dose and for Aboriginal and non-Aboriginal children. RESULTS: Each dose-specific cohort included at least 49,000 Aboriginal and 1.1 million non-Aboriginal children. Delayed receipt was more common among Aboriginal than non-Aboriginal children (eg for the first dose of DTP [DTP1] 19.4 v 8.1%). Risk factors for delayed vaccination were strongest for DTP1, and delayed receipt of DTP1 was a key driver of subsequent delays; every week DTP1 was delayed was associated with a 1.6 to 2-fold increased risk of delayed DTP2 receipt. For DTP1, ≥3 previous pregnancies (the only factor more strongly associated with longer than shorter delays; RR ≥5 compared to no previous pregnancies), and children born to mothers <20 years of age (RR ≥2 compared to ≥35 years) were at highest risk of delay. Other independent predictors were prematurity, maternal smoking during pregnancy, and being born in Western Australia (if Aboriginal) or another country in the Oceania region. CONCLUSION: The sub-populations at risk for delayed vaccination we have identified are likely generalisable to other high-income settings. Measures to improve their dose 1 timeliness, particularly for children with older siblings, are likely to have significant flow-on benefits for timeliness of later doses.

Annual Immunisation Coverage Report 2017.

This eleventh national annual immunisation coverage report focuses on data for the calendar year 2017 derived from the Australian Immunisation Register (AIR) and the National Human Papillomavirus (HPV) Vaccination Program Register. This is the first report to include data on HPV vaccine course completion in Aboriginal and Torres Strait Islander (Indigenous) adolescents. 'Fully immunised' vaccination coverage in 2017 increased at the 12-month assessment age reaching 93.8% in December 2017, and at the 60-month assessment age reaching 94.5%. 'Fully immunised' coverage at the 24-month assessment age decreased slightly to 89.8% in December 2017, following amendment in December 2016 to require the fourth DTPa vaccine dose at 18 months. 'Fully immunised' coverage at 12 and 60 months of age in Indigenous children reached the highest ever recorded levels of 93.2% and 96.9% in December 2017. Catch-up vaccination activity for the second dose of measles-mumps-rubella-containing vaccine was considerably higher in 2017 for Indigenous compared to non-Indigenous adolescents aged 10-19 years (20.3% vs. 6.4%, respectively, of those who had not previously received that dose). In 2017, 80.2% of females and 75.9% of males aged 15 years had received a full course of three doses of human papillomavirus (HPV) vaccine. Of those who received dose one, 79% and 77% respectively of Indigenous girls and boys aged 15 years in 2017 completed three doses, compared to 91% and 90% of non-Indigenous girls and boys, respectively. A separate future report is planned to present adult AIR data and to assess completeness of reporting.

Annual Immunisation Coverage Report 2016.

This tenth annual immunisation coverage report shows data for the calendar year 2016 derived from the Australian Immunisation Register (AIR) and the National Human Papillomavirus (HPV) Vaccination Program Register. After a decade of being largely stable at around 90%, 'fully immunised' coverage at the 12-month assessment age increased in 2016 to reach 93.7% for the age assessment quarterly data point in December 2016, similar to the 93.4% for the age assessment quarterly data point in December 2016 for 60 months of age. Implementation of the 'No Jab No Pay' policy may have contributed to these increases. While 'fully immunised' coverage at the 24-month age assessment milestone decreased marginally from 90.8%, in December 2015, to 89.6% for the age assessment quarterly data point in December 2016, this was likely due to the assessment algorithm being amended in December 2016 to include four doses of DTPa vaccine instead of three, following reintroduction of the 18-month booster dose. Among Indigenous children, the gap in coverage assessed at 12 months of age decreased fourfold, from 6.7 percentage points in March 2013 to only 1.7 percentage points lower than non-Indigenous children in December 2016. Since late 2012, 'fully immunised' coverage among Indigenous children at 60 months of age has been higher than for non-Indigenous children. Vaccine coverage for the nationally funded seasonal influenza vaccine program for Indigenous children aged 6 months to <5 years, which commenced in 2015, remained suboptimal nationally in 2016 at 11.6%. Changes in MMR coverage in adolescents were evaluated for the first time. Of the 411,157 ten- to nineteen-year-olds who were not recorded as receiving a second dose of MMR vaccine by 31 December 2015, 43,103 (10.5%) of them had received it by the end of 2016. Many of these catch-up doses are likely to have been administered as a result of the introduction on 1 January 2016 of the Australian Government's 'No Jab No Pay' policy. In 2016, 78.6% of girls aged 15 years had three documented doses of HPV vaccine (jurisdictional range 67.8-82.9%), whereas 72.9% of boys (up from 67.1 % in 2015) had received three doses.

Immunisation coverage annual report, 2015

This 9th annual immunisation coverage report shows data for 2015 derived from the Australian Childhood Immunisation Register and the National Human Papillomavirus (HPV) Vaccination Program Register. This report includes coverage data for 'fully immunised' and by individual vaccines at standard age milestones and timeliness of receipt at earlier ages according to Indigenous status. Overall, 'fully immunised' coverage has been mostly stable at the 12- and 24-month age milestones since late 2003, but at 60 months of age, coverage reached its highest ever level of 93% during 2015. As in previous years, coverage for 'fully immunised' at 12 and 24 months of age among Indigenous children was 3.4% and 3.3% lower than for non-Indigenous children overall, respectively. In 2015, 77.8% of Australian females aged 15 years had 3 documented doses of HPV vaccine (jurisdictional range 68.0­85.6%), and 86.2% had at least one dose, compared to 73.4% and 82.7%, respectively, in 2014. The differential of on-time vaccination between Indigenous and non-Indigenous children in 2015 diminished progressively from 18.4% for vaccines due at 12 months to 15.7% for those due at 24 months of age. In 2015, the proportion of children whose parents had registered an objection to vaccination was 1.2% at the national level, with large regional variations. This was a marked decrease from 1.8% in 2014 and the lowest rate of registered vaccination objection nationally since 2007 when it was 1.1%. Medical contraindication exemptions for Australia were more than double in 2015 compared with the previous year (635 to 1,401).

Closing the vaccination coverage gap in New South Wales: the Aboriginal Immunisation Healthcare Worker Program.

OBJECTIVES: To assess vaccination coverage and timeliness among Indigenous and non-Indigenous children in New South Wales and the rest of Australia, with a particular focus on changes in the vaccination coverage gaps after the introduction of the Aboriginal Immunisation Healthcare Worker (AIHCW) Program in NSW in 2012. DESIGN: Cross-sectional analysis of Australian Immunisation Register data (2008-2016). MAIN OUTCOME MEASURES: Annual estimates of full vaccination coverage at 9, 15 and 51 months of age for Indigenous and non-Indigenous children in NSW and the rest of Australia; differences in coverage between Indigenous and non-Indigenous children at each milestone. RESULTS: The proportion of Indigenous and non-Indigenous children classified as fully vaccinated at 9, 15, and 51 months increased significantly in both NSW and the rest of Australia after the introduction of the AIHCW Program. The mean annual difference in full vaccination coverage between Indigenous and non-Indigenous children in NSW aged 9 months declined from 6.6 (95% CI, 5.2-8.0) during 2008-2011 to 3.7 percentage points (95% CI, 2.5-4.8) during 2012-2016; for those aged 15 months it declined from 4.6 (95% CI, 3.1-6.0) to 2.2 percentage points (95% CI, 1.0-3.4), and for those aged 51 months it declined from 8.5 (95% CI, 7.2-9.8) to 0.6 percentage points (95% CI, -0.6 to 1.8). Reductions in the differences in coverage were not as marked in the rest of Australia. In 2016, there was no statistically significant difference in coverage at any of the three milestones in NSW: at 9 months the difference was 1.6 percentage points (95% CI, -1.0 to 4.1); at 15 months, 0.4 percentage points (95% CI, -2.2 to 2.9); and at 51 months, -1.8 percentage points (95% CI, -4.4 to 0.8). CONCLUSION: Our findings suggest that a dedicated program can help overcome barriers to timely vaccination and significantly improve timely vaccination rates in Indigenous Australian children.

Evaluation of Combination Measles-Mumps-Rubella-Varicella Vaccine Introduction in Australia.

Importance: Incorporating combination vaccines, such as the measles-mumps-rubella-varicella (MMRV) vaccine, into immunization schedules should be evaluated from a benefit-risk perspective. Use of MMRV vaccine poses challenges due to a recognized increased risk of febrile seizures (FSs) when used as the first dose in the second year of life. Conversely, completion by age 2 years of measles, mumps, rubella, and varicella immunization may offer improved disease control. Objective: To evaluate the effect on safety and coverage of earlier (age 18 months) scheduling of MMRV vaccine as the second dose of measles-containing vaccine (MCV) in Australia. Design, Setting, and Participants: Prospective active sentinel safety surveillance comparing the relative incidence (RI) of FSs in toddlers given MMRV and measles-mumps-rubella (MMR) and a national cohort study of vaccine coverage rates and timeliness before and after MMRV vaccine introduction were conducted. All Australian children aged 11 to 72 months were included in the coverage analysis, and 1471 Australian children aged 11 to 59 months were included in the FS analysis, with a focus on those aged 11 to 23 months. Main Outcomes and Measures: MMRV vaccine safety, specifically, the RI of FSs after MMRV vaccine at age 18 months, compared with risk following MMR vaccine and vaccine uptake for 2-dose MCV and single-dose varicella vaccine, focusing on timeliness. Results: Of the 1471 children, the median age at first FS was 21 months (interquartile range [IQR], 14-31 months). Three hundred ninety-one children were aged 11 to 23 months and had at least 1 FS included in the analysis; of these, 207 (52.9%) were male. A total of 278 children (71.1%) had received MMR followed by MMRV vaccine, 97 (24.8%) had received MMR vaccine only, and 16 (4.1%) had received neither vaccine. There was no increased risk of FSs (RI, 1.08; 95% CI, 0.55-2.13) in the 5 to 12 days following MMRV vaccine given as the second MCV to toddlers. Febrile seizures occurred after dose 1 of MMR vaccine at a known low increased risk (RI, 2.71; 95% CI, 1.71- 4.29). Following program implementation, 2-dose MCV coverage at age 36 months exceeded that obtained at age 60 months in historical cohorts recommended to receive MMR vaccine before school entry, and on-time vaccination increased by 13.5% (from 58.9% to 72.4%). Despite no change in the scheduled age of varicella vaccine, use of MMRV vaccine was associated with a 4.0% increase in 1-dose varicella vaccine coverage. Conclusions and Relevance: To our knowledge, this is the first study to provide evidence of the absence of an association between use of MMRV vaccine as the second dose of MCV in toddlers and an increased risk of FSs. Incorporation of MMRV vaccine has facilitated improvements in vaccine coverage that will potentially improve disease control.

Impact and effectiveness of childhood varicella vaccine program in Queensland, Australia.

BACKGROUND: In November 2005, Australia introduced a publicly funded single dose of varicella vaccine for children aged 18-months. We describe the impact of this program on varicella hospitalisations in Queensland and provide the first assessment of single-dose varicella vaccine effectiveness in Australia since the program commenced. METHODS: Age-standardised varicella hospitalisation rates were calculated for 2000-2014 and pre- and post-public funding period rates compared. Case-control studies were conducted to investigate the association between vaccine receipt and both varicella hospitalisations and uncomplicated varicella emergency department presentations. Cases were matched to controls from a population-based register by date of birth and state of residence. Vaccine effectiveness was calculated as (1-odds ratio)×100%. RESULTS: Compared to the pre-funded period (2000-2003), age-standardised varicella hospitalisation rates declined by more than 70% in 2011-2014 with varicella principal diagnosis rates declining from 5.7 to 1.6 per 100,000 population per year. Varicella vaccine effectiveness at preventing hospitalisation with a principal diagnosis of varicella among children aged 19-months to 6-years was 81.9% (95% confidence interval: 61.8-91.4%), while for emergency department presentations among children aged 19-months to 8-years it was 57.9% (95% confidence interval: 48.5-65.5%). CONCLUSIONS: In Australia, the single-dose varicella vaccination program has substantially reduced varicella morbidity. The single-dose varicella vaccine schedule is moderately-to-highly effective against hospitalisation, but appears less effective against emergency department presentations.

Immunisation coverage annual report, 2014.

This 8th annual immunisation coverage report shows data for 2014 derived from the Australian Childhood Immunisation Register and the National Human Papillomavirus Vaccination Program Register. This report includes coverage data for 'fully immunised' and by individual vaccines at standard age milestones and timeliness of receipt at earlier ages according to Indigenous status. Overall, 'fully immunised' coverage has been mostly stable at the 12- and 24-month age milestones since late 2003, but at 60 months of age, it has increased by more than 10 percentage points since 2009. As in previous years, coverage for 'fully immunised' at 12 months of age among Indigenous children was 3.7% lower than for non-Indigenous children overall, varying from 6.9 percentage points in Western Australia to 0.3 of a percentage point in the Australian Capital Territory. In 2014, 73.4% of Australian females aged 15 years had 3 documented doses of human papillomavirus vaccine (jurisdictional range 67.7% to 77.4%), and 82.7% had at least 1 dose, compared with 71.4% and 81.5%, respectively, in 2013. The disparity in on-time vaccination between Indigenous and non-Indigenous children in 2014 diminished progressively from 20.2% for vaccines due by 12 months to 11.5% for those due by 24 months and 3.0% at 60 months of age.

Trends and patterns in vaccination objection, Australia, 2002-2013.

OBJECTIVES: To examine geographic and demographic trends in objection to vaccination in Australia. DESIGN: Cross-sectional analysis of Australian Childhood Immunisation Register (ACIR) data (2002-2013) for children aged 1-6 years. MAIN OUTCOME MEASURES: Immunisation status according to whether an objection had been registered, and remoteness and socio-economic status of area of residence. Registration of children with Medicare after 12 months of age was used as a proxy indicator of being overseas-born. RESULTS: The proportion of children affected by a registered vaccination objection increased from 1.1% in 2002 to 2.0% in 2013. Children with a registered objection were clustered in regional areas. The proportion was lower among children living in areas in the lowest decile of socio-economic status (1.1%) than in areas in the highest socio-economic decile (1.9%). The proportion not affected by a recorded objection but who were only partly vaccinated for vaccines due at 2, 4 and 6 months of age was higher among those in the lowest decile (5.0% v 3.4%), suggesting problems of access to health services, missed opportunities, and logistic difficulties. The proportion of proxy overseas-born for whom neither vaccinations nor an objection were recorded was 14 times higher than for other children (17.1% v 1.2%). These children, who are likely to be vaccinated although this is not recorded on the ACIR, resided predominantly in major cities. CONCLUSIONS: There was a small increase in registered objection rates since 2002. We estimate that 3.3% of children are affected by registered or presumptive (unregistered) vaccination objection, which suggests that the overall impact of vaccination objection on vaccination rates has remained largely unchanged since 2001. Incomplete records, barriers to access, and missed opportunities are likely to be responsible for most other deficiencies in vaccination coverage.