For universally recommended childhood vaccines, Aboriginal and Torres Strait Islander children continue to have lower vaccination coverage at 12 months of age than other children. The difference in ‘fully vaccinated’ coverage, using the ‘old’ (1996 – June 2013) definition, was 6 percentage points during this reporting period. By 24 months of age, the difference was less than 1 percentage points. As no vaccines given between 12 and 24 months of age were included in this calculation, this suggests the role of a higher level of delayed vaccination in Aboriginal and Torres Strait Islander children than in other children. Coverage for the pre-school doses due at 4 years of age reflects a similar situation. Between 2003 and 2006, when ‘fully vaccinated’ coverage was measured at 72 months (6 years) of age, it was comparable between Aboriginal and Torres Strait Islander and other children. However, in this report, where coverage is now measured at 60 months (5 years) of age, it is 4 percentage points lower in Aboriginal and Torres Strait Islander children than in other children.
However, there have been improvements in recent years. The promotion of administering the first dose at 6 weeks of age in New South Wales and Tasmania in 2009 was effective in both Aboriginal and Torres Strait Islander and other children. Also in 2009, the change in due and overdue rules for the pre-school doses, which classified children as overdue at 4 years and 1 month instead of 5 years of age, resulted in substantial improvements in timeliness in Aboriginal and Torres Strait Islander and other children. Improvements over time have also been seen in coverage for all children for doses due at 12 months of age, although this does not appear to be directly related to a specific policy initiative. For individual vaccines, coverage estimates are quite similar to those for ‘fully vaccinated’, with the exceptions of rotavirus and varicella vaccines. Rotavirus vaccine coverage at 12 months of age in ‘other’ infants is 6–9 percentage points lower than for other vaccines given at this milestone. This is probably a result of the strict upper age limits for administering these vaccines, as infants arriving too late to receive rotavirus vaccine can still receive other vaccines. However, for Aboriginal and Torres Strait Islander infants, this discrepancy is more marked in areas using a 3-dose schedule, where the proportion of Aboriginal and Torres Strait Islander infants who have received rotavirus vaccine by 12 months of age is 17 percentage points lower than in other infants. Varicella vaccine coverage by 24 months of age is lower than for other vaccines, but there is little difference in coverage between Aboriginal and Torres Strait Islander and other children. This underlines the importance of continuing to monitor, and have access to, coverage data on vaccines not included in the ‘fully vaccinated’ definition.
Coverage for vaccines recommended only for Aboriginal and Torres Strait Islander children continues to be substantially lower than that for universal vaccines, as shown in this report for hepatitis A vaccine and pneumococcal vaccine boosters. Both these vaccines are limited to the Northern Territory, Queensland, South Australia and Western Australia. Coverage varies much more substantially between jurisdictions for these vaccines than for universally recommended vaccines. This underlines the importance of immunisation providers establishing the Indigenous status of their clients, particularly in urban areas, so they can offer them the additional vaccines they may require.
There has been relatively little research on the specific causes of low coverage and delayed vaccination in Indigenous people worldwide. Greater mobility of Aboriginal and Torres Strait Islander people may contribute in some instances. However, the evidence suggests many of the barriers are those common to people of low socioeconomic status.123,124 Measures that are effective in other settings can also be effective in Indigenous communities; these include the elimination of financial barriers, vaccination by non-medical staff, patient and provider education, patient reminders, diverse delivery models such as outreach and inpatient as well as primary care,125 and clinical quality improvement activities. The introduction of a personalised calendar to improve timeliness is an Australian example of the successful implementation of a measure that had been effective in other settings being applied to Aboriginal and Torres Strait Islander children.126 The use of Medicare items for child and adult health checks for Aboriginal and Torres Strait Islander people can also be effective for catch-up vaccination.127 Monitoring milestones earlier than at 12 months of age may also be worth consideration.128
Unlike previous editions of this report, updated data from the National Aboriginal and Torres Strait Islander Health Survey was not available. At the time of writing a survey was in progress, the first since the 2004/2005 survey reported on in our previous edition. The only other data on Aboriginal and Torres Strait Islander adult vaccination coverage available during this 8-year gap were from the 2009 Adult Vaccination Survey. This survey estimated coverage of 23% for the pandemic H1N1 vaccine and 28% for the 2009 seasonal influenza vaccine among Aboriginal and Torres Strait Islander people aged ≥18 years.117 No coverage data are available for the first 2 years of funded influenza vaccine for Aboriginal and Torres Strait Islander people aged ≥15 years. This highlights the need for more frequent and detailed data to support program managers.
For Aboriginal and Torres Strait Islander adolescents, no vaccine coverage data have been published or publicly released.
Indigenous status is collected on the National HPV Register but this has not been included in HPV coverage data released to date. Coverage data for the general adolescent population for vaccines other than HPV are not collated nationally, and are infrequently published by states and territories. New Zealand Maori adolescents have been shown to have lower consent form returns and lower vaccination rates from school-based programs.129 A similar finding in Australia for Aboriginal and Torres Strait Islander adolescents would not be unexpected. Given the focus on school-based delivery and lower rates of school attendance by Aboriginal and Torres Strait Islander students,130 good coverage data for this age group are urgently needed.
This publication is available as a downloadable document.