Immunisation coverage How much do we need? How do we get there?

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1 Immunisation coverage How much do we need? How do we get there? Peter McIntyre Director, NCIRS Julie Leask Associate Professor University of Sydney and ghost writer

2 Topics and questions Evidence about diseases and vaccines What does high vaccine coverage achieve? herd immunity threshold Coverage and what works to maximise it Low coverage regions Proven strategies for increasing coverage

3 Vaccine coverage and herd immunity Measles vs Pertussis examples

4 Infectiousness and transmission Pertussis Ro 5-17 Measles Ro Both need 95% coverage or above to control Transmission

5 Measles and pertussis vaccines Measles vaccine Live vaccine, prevents infection cases almost always unvaccinated No home grown measles circulating in Australia Measles from overseas finds non-immunes despite high general community coverage Pertussis vaccine Inactivated vaccine does not prevent infection Protects against severe disease Milder cases often vaccinated (waning immunity) Pertussis always circulating periodic increases

6 What does herd immunity achieve? High coverage protects those who cannot be protected by vaccine themselves Immune compromised Non responders to vaccine (measles ~ 5-10%) Can achieve disease elimination Smallpox - worldwide Polio - Australia Measles Australia

7 What can t be achieved with herd immunity? Protecting non-immune people who travel overseas or are exposed to infected travellers Measles Diphtheria Polio Vaccines which do not confer herd immunity Tetanus Protect babies too young for vaccination Maternal pertussis

8 Deaths from pertussis per million < 5 years 1926 to 2012

9 Deaths from pertussis 1967 to 2013

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11 Vaccine coverage and vaccine refusal

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14 Coverage in Australia at 24 months of age

15 Numbers of registered objectors cumulative totals

16 Percentage of vaccine objectors 3.5 Trends in vaccine objection Absolute change of 0.5 of a percentage point from 2002 Absolute change of 0.4 of a percentage point from Year Objection and no vaccines recorded No objection & no vaccines recorded Objection and at least one vaccine recorded

17 Percentage Vaccine objection by socio-economic status Top 10% SES v Bottom 10% SES postcodes (born Jan 07 Dec 12) Objection and no vaccines recorded Objection and at least one vaccine recorded No objection & no vaccines recorded No objection & not fully immunised at 12mo Bottom 10% (low SES postcodes) Top 10% (high SES postcodes)

18 Vaccine objectors cluster Source; Brynley Hull, NCIRS Unpubli

19 Percentage Vaccine objection % in high objector areas 2013 (cohort born Jan 07 Dec 12) Objection and no vaccines recorded Objection and at least one vaccine recorded No objection & no vaccines recorded No objection & not fully immunised at 12mo Richmond Valley - Coastal NSW Adelaide Hills Sunshine Coast Hinterland QLD Tablelands East - Kuranda QLD

20 % of postcodes Percentage of postcodes with MMR coverage < 95% 100% Percent of eligible postcodes (n~1490) at different levels of coverage for one dose of MMR assessed at 6 years of age in Australia, % 80% % 60% 50% % 30% % % 0% Year Level of MMR1 coverage (%) < < < < 90

21 What works to increase coverage?

22 Leask (unpublished) From Benin et al., Pediatrics, 2006, Downs et al., Vaccine, Gust et al Am J Health Behav Parental Attitudes Pyramid I didn t want to put anything unnatural in him I was in two minds. I did get Leo vaccinated within the recommended time frame Refuser s Late or selective Hesitant Cautious acceptors As a Mama I practice breastfeeding, baby sign, selective, delayed vaccinating, and elimination communication Unquestioning acceptors

23 Layers of lack of opportunity Vaccine supply Eligibility policies Incompatible schedules Differing cultural perspectives on health Clinic hours Provider false contraindications Lack of cultural respect Itinerant housing Home-bound Out-of-home care Sick child Competing priorities Bereavement Not aware vaccine is due Source:

24 Childhood immunisation incentives for parents and providers

25 Conscientious objectors.. on the rise No longer eligible for child-care benefit rebate and family tax rebate

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27 Exemptions to School Immunization Laws United States TYPE OF EXEMPTION(S) ALLOWED Philosophic, Religious & Medical (20) Religious & Medical (28) Medical only (2) updated March

28 Payment for GPs to catch up children with delayed vaccines Adolescent register (school-based vaccines) Materials to support immunisation - especially for hesitant parents 19/child-vaccination-package-26- million-federal-governmentunveiled/

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30 Enhancing Access to Vaccination Services Home Visits to Increase Vaccination Rates Reducing Out-of-Pocket Costs Programs in Schools and Child Care Centres Increasing Community Demand for Vaccination Reminder and Recall Systems Requirements for Child Care and School Attendance Insufficient Evidence Clinic-Based or Community Education Alone Monetary Sanction Policies Provider- or System-Based Interventions Immunization Information Systems Provider Assessment and Feedback Provider Reminders Insufficient Evidence Provider Education Alone Sources: 1.Ward K, Chow MYK, King C, Leask J. Australian and New Zealand Journal of Public Health 2012; 36(4): The Community Guide cines/index.html

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32 Personal stories of regret from NZ

33 Summary Important differences by disease and vaccine Measles is the most severe test of vaccine coverage and herd protection anything short of 100% coverage everywhere is a chink in our armour Proven strategies to maximise infant and child coverage have been identified in Australia and internationally best employed together Challenges and opportunities in implementation and advocacy await - particularly for the high risk and under served populations being studied by the Centre for Research

34 Acknowledgements A/Prof Julie Leask A/Prof Kristine Macartney Dr Kerrie Wiley NCIRS staff