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Title: Priscilla KincaidSmith Oration:


1
Priscilla Kincaid-Smith Oration
  • Sponsored by

2
Vaccines Value For Future Health
  • Terry Nolan

Chair Robin Mortimer
3
(No Transcript)
4
Pneumococcal sepsis
5
Deaths in Australia, 1926-97
6
Diphtheria, 1917-2000
7
Tetanus, 1917-2000
8
Poliomyelitis, 1917-2000
9
Rubella, 1917-2000
10
Pertussis notifications and hospitalisations,
Australia,1993 to 2000, by month of onset or
admission
11
Rubella notifications and hospitalisations,
Australia,1993 to 2000, by month of onset or
admission
Note varying scales between notifications and
hospitalisations
12
Trends in vaccination coverage estimates from the
Australian Childhood Immunisation Register for 1
and 2 year olds
Source Australian Childhood Immunisation Register
13
What went wrong?
  • Success made immunisation unfashionable
  • Lost national coordinated approach
  • Commonwealth delegated population immunisation
    role to States
  • Public and health professional complacency
  • Pertussis vaccine safety concerns
  • No program management, no useful data on coverage
  • No research on new vaccines, on delivery or on
    program effectiveness

14
New strategies
  • NHMRC National Strategy
  • Commonwealth resumed leadership
  • Australian Childhood Immunisation register (ACIR)
  • New Government priority
  • Immunise Australias 7-point plan
  • Incentives for parents providers
  • Mobilisation of primary care workforce
  • Better vaccines and combinations

15
Australian Childhood Immunisation Register (ACIR)
  • Introduced in 1990s to facilitate tracking
  • Established within Health Insurance Commission
  • Recall and reminder system
  • Look-up system for providers
  • Monitor healthcare provider performance
  • Monitor population uptake
  • 6 payment per notification

16
Challenges of the 1990s
  • New vaccines emerged
  • Hepatitis B vaccine, conjugate Hib vaccine
  • Conjugate pneumococcal and meningococcal vaccines
  • Consumers wanted better vaccines
  • Fewer adverse effects
  • Acellular pertussis vaccine
  • IPV versus OPV and vaccine associated polio
  • Healthcare providers wanted efficiency
  • Fewer jabs
  • Simpler administration

17
Effective immunisation is more than just a good
vaccine
The hepatitis B vaccine story
18
Hepatitis B vaccination of adolescents in
Australia
  • Prevalence lt 1
  • Incidence 1.6 / 100,000
  • Peak incidence at ages 15 34 y
  • Marked increase in this age group in 2000
  • Universal immunisation cost-effective
  • Infant/ adolescent program saves 443 life-years
    for net cost-saving of A1.63 million
  • Adolescent program saves 404 life-years for 4.57
    million

National acute cases reported 1993-1998
(McIntyre et al, 2000) Cost-effectiveness
analysis for NHMRC working party (Butler, 1996)
19
Hepatitis B mass vaccination in Australia
  • 1997 NHMRC recommended universal infant and
    young adolescent immunisation
  • 1998 11-13 year olds
  • Adolescent school-based delivery
  • Victoria, S.A. and Tasmania (mix)
  • Adolescent GP delivery
  • NSW, QLD, WA
  • 2000 birth dose and infant program (combination
    vaccines available)

20
Victorian birth dose study
  • Survey of all maternity hospitals in Victoria (n
    98) 1 July 2000 - 31 December 2000.
  • Responses received from 93 hospitals, covering
    99 of Victorian births in that period.
  • Vaccine uptake estimated at 85.
  • HIC now planning ACIR pilot of direct reporting
    from hospitals.

Source Kathryn Whitfield and Rosemary Lester,
DHS Victoria unpublished
21
Infant uptake in Australia
  • Based on Australian Childhood Immunisation
    Register (ACIR), which under-estimates by 2.7 at
    12 months of age
  • 94 coverage of all schedule vaccines at 12
    months of age
  • DTPa-hepB course completed at 6 months, Hib-hepB
    course completed at 12 months
  • Only 2-3 of parents object to immunisation at 12
    months of age

22
Immunisation of adolescents
  • Developmental process of adolescence militates
    against compliance with health preventive
    strategies
  • Poor uptake in non-compulsory adolescent
    programs, with exceptions
  • Adolescents have few interactions with GPs for
    health care
  • Little known about modifiers of immunisation
    compliance in adolescence

23
Adolescent uptake in Australia
  • School-based
  • Vic
  • 2001, 81 of adolescents first dose, 75 second
    dose.
  • SA
  • 2001, 88 dose 1, 81 3 doses.
  • Tas
  • No data available (GPs and councils)
  • GPs
  • QLD
  • VIVAS data not reliable, estimate lt30 dose 1
  • WA
  • No data available
  • NSW

24
NSW experience
  • NSW Health CATI survey
  • 1567 households with children aged 10 - 13 years,
    n1900.
  • Verified against blue book.
  • 17.9 ever received a Hep B vaccine
  • Of these, 70 had received a complete course,
    making complete course uptake 12.6
  • 70 had been vaccinated prior to 10 years of age.
  • i.e. only about 9 being completely vaccinated at
    recommended time.

25
Clinic-based hepatitis B vaccination programs
26
Hepatitis B school-based programs
all non-compulsory
27
Cost-effectiveness of school-based delivery for
adolescents
  • NSW data show clear cost savings over
    GP-administered program
  • Leon Herron (unpublished)

28
Conclusions
  • Birth dose program moderately successful in
    Victoria. Reliable data not available for other
    States.
  • Infant uptake high and at level of population
    target.
  • Catch-up program for adolescents failing in
    States that do not yet deliver through schools.
  • Where school implementation effective, add-on
    promotion activity not necessary to achieve high
    uptake levels1.

1Skinner, R.S., Imberger, I., Lester, R., Glover,
S., Bowes, G., Nolan, T.M. Randomised controlled
trial of an educational strategy to increase
school-based adolescent hepatitis B vaccination.
Australian and New Zealand Journal of Public
Health 200024298-304.
29
Are we doing enough about hep B?
No, we are not
  • Birth dose program monitoring needs to be fixed
  • School- based delivery for adolescents
  • Overwhelming evidence
  • Cheaper and more cost-effective than GP
  • Conjugate men C program may facilitate
    introduction of school programs in NSW and QLD
  • High school entry law
  • Targeted home immunisation further enhances
    high-uptake school-based immunisation in
    adolescence

30
Scheduling funding population vaccines in
Australia
31
Concept of the Australian Standard Vaccination
Schedule (ASVS)
  • Expressed both in practice and in the NHMRC
    National Immunisation Strategy of 1993
  • Coordinated approach under Commonwealth
    leadership, central funding of vaccines, central
    policy advice (ATAGI), nationally led consortium
    of State and primary care providers (NIC)
  • The Schedule was essentially restricted to
    publicly funded universally available vaccines
  • Major change, accepted by Government and soon to
    be endorsed by NHMRC is concept of best practice,
    evidence-based ASVS.
  • That is, public funding not a requirement for
    ASVS listing
  • Implications for providers and consumers.

32
ATAGI, NHMRC and the basis for recommendations
  • Multidimensional, evidence-based assessment
  • Evidence regarding
  • Vaccine efficacy data, ideally from RCTs
  • Vaccine safety
  • Impact on disease burden reduction (mortality,
    morbidity, health service use)
  • Health economic evaluation (CEA)
  • Vaccine cost assessment
  • Supply, quality, reliability
  • Ethics and equity issues

33
Health economic analysis (cost-effectiveness
ratio) and vaccine value assessment
  • Same basis for value assessment as drugs and
    other health interventions (PBAC)
  • Requires cabinet approval if gt10m
  • Common metric permits benchmarking against
    competitors for the health dollar
  • Incorporates direct health care costs, but not
    societal or indirect costs (lost work, parent
    time, other opportunity costs)
  • Substantial disadvantage for high prevalence, low
    severity illnesses that still have large
    community impact (e.g. influenza, varicella).

34
Public sector vaccine prices
Prices in AUD, include GST price when formerly
used
35
Immunisation policy development in Australia
36
Ethics and Litigation
  • Vaccine-associated polio (VAPP) risk about 1 case
    expected every 3 years in Australia
  • Case-finding now intensified because of WHO
    effort towards pre-eradication declaration of
    polio-free status
  • Now doubtful whether will be able to stop because
    of bioterrorism risk
  • A single case of VAPP could do enormous damage to
    the national program and consumer confidence
  • Ethics of mass program with known non-zero risk
    of major adverse event

37
Vaccine injury litigation in Australia
  • Feared litigation epidemic has not occurred
  • Still at risk of massive awards in single cases
  • No-fault compensation scheme needs further
    serious consideration despite substantial safety
    track record of vaccines

Its not very far away
38
Supply issues and the critical role of industry
  • Availability
  • Market share and multiple suppliers
  • Dependence and risk exposure
  • Lead-time issues forward planning
  • Little Australian industry
  • Complexity of State and Fed purchasing
  • ? Implications of free trade agreement with USA

39
Changes to ASVS 2003
  • The fourth dose of DTPa at 18 months now dropped.
  • Low antigen formulation pertussis-containing
    vaccine (dTpa) recommended as a single dose at 15
    to 17 years.
  • Oral poliomyelitis vaccine (OPV) is replaced by
    inactivated poliomyelitis vaccine (IPV) for the
    3-dose primary series (2, 4 and 6 months of age)
    and for the booster dose at 4 years of age. All
    doses of IPV are provided in the form of
    combinations with other vaccines (DTPa-hepB-IPV,
    DTPa-IPV, DTPa-IPV-Hib, DTPa-IPV-hepB-Hib).
  • 7-valent pneumococcal conjugate vaccine (7vPCV)
    is recommended for all Australian children as a
    3-dose series at 2, 4 and 6 months.
  • Meningococcal C conjugate vaccine (MenCCV) is
    recommended as a single dose at 12 months of age
    and at the age of 15 years who have not
    previously received the conjugate vaccine
    (superseded by Government policy).
  • Varicella vaccine for all children at 18 months
    of age, with a catch-up dose for adolescents 10
    to 13 years of age without a history of either
    varicella or varicella vaccination.

40
Proposed ASVS
41
Evaluation of candidate ASVS vaccines
42
Impact of vaccination
43
Summary of epidemiology in developed world
settings
  • Right-shift in age distribution with increasing
    number and proportion of pertussis cases in
    adolescents and adults
  • Outbreak investigations show high attack rates in
    adolescents and adults
  • Evidence of waning immunity in naturally infected
    as well as whole-cell pertussis immunised adults
  • About 1 in 4 adults with prolonged cough have
    serologic evidence of recent pertussis infection
  • Adults and adolescents in the home are the most
    frequent source of infection of infants who have
    highest mortality and morbidity

44
Pertussis notificationsAustralia 2000, rate per
100,000
45
Pertussis notifications by age, 1993-2001
Increased incidence in 15y and infants
Source National Centre for Immunisation Research
and Surveillance
46
Pertussis deaths
47
Italian NIH study
  • 3 doses of 3-component DTaP (GSK or Chiron) or DT
    vaccines
  • Pertussis toxin (PT), filamentous hemagglutinin
    (FHA) and pertactin in both DTaP vaccines
  • 2, 4 and 6 months of age
  • DTaP efficacy 84 in first 2 years of life
  • Stage 2 follow-up at 33 months showed similar
    efficacy
  • Stage 3 follow-up ages 3-6 years in over 9,500
    children, mean age 5.8 years.

Salmaso et al. Pediatrics 2001108(5).
http//www.pediatrics.org/cgi/content/full/108/5/e
81
48
Vaccine efficacy estimates ()(NIH Italian study)
Salmaso et al. Pediatrics 2001108(5).
http//www.pediatrics.org/cgi/content/full/108/5/e
81
49
History of pertussis boosters in Australia since
1980s
18 month booster
  • DTwP booster dropped in early 1980s
  • Concern re pertussis encephalopathy
  • Surge in hospitalised infants with pertussis
  • Rapidly re-introduced
  • DTwP replaces DTaP as booster in 1998, about a
    year before DTaP replaces DTwP in primary course
    (2, 4 and 6 months of age)

50
History of pertussis boosters in Australia since
1980s
Pre-school booster
  • DTwP introduced as 5th dose in 1994, then DTaP
    replaced DTwP in 1999
  • High levels of adverse effects and school absence
    after DTwP
  • Uptake now good for DTaP at 5yrs
  • High level of parent acceptance and support for
    government provision of free vaccine, even though
    more expensive

51
History of pertussis vaccine boosters in
Australia since 1980s
Adolescent booster
  • dT delivered now
  • ATAGI recommendation for pertussis booster under
    consideration by Government

52
Population modelling
  • Adult boosting every 10 years should reduce
    number and severity of adult pertussis infections
  • But, mathematical modelling suggests that adult
    boosting will only produce modest reduction in
    pertussis in infants and children through herd
    effects.

53
Hethcote population adult pertussis booster model
54
What about a cocoon strategy to protect against
infant pertussis deaths?
  • Idea is to vaccinate all family members of
    expectant mothers (including extended family)
  • Protect the newborn by immunising all those who
    have contact before the age of 6 months (when
    infant primary course should be completed)
  • Epidemiologic evidence suggests that this could
    work
  • However, not yet demonstrated or evaluated
  • Renewed interest in neonatal immunisation with
    acellular vaccines, but studies not yet done.

55
Varicella vaccine and zoster protection Lesson 2
56
Lack of boosting and Zoster
  • Possible effect of reduced wild virus boosting of
    naturally infected individuals if high vaccine
    uptake is achieved in children.
  • Epidemiologic evidence shows that contact with
    children who have chicken-pox protects against
    zoster in adults.
  • Immunologic evidence shows that intimate exposure
    to children with varicella boosts VZV-specific
    CMI in seropositive adults.
  • Recent modelling studies predict that the
    lifetime risk of zoster will be over 50 in those
    aged 10-44 years at the introduction of mass
    vaccination.

57
Epidemiologic evidence and boosting
58
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59
Brisson et al. Vaccine 2002202500-7.
60
Brisson et al. Vaccine 2002202500-7.
61
Brisson et al. Vaccine 2002202500-7.
62
Left shift in age of zoster
  • May actually be (net) beneficial
  • Less severe episodes at younger age
  • May have higher risk of second episode but each
    may be less severe.
  • Lower net burden possible.
  • Will vaccination of naturally infected adults
    prevent zoster?
  • US Veterans Cooperative Study results in 2004
  • Enrolled 38,546 aged 60y
  • High release titre VZV vaccine vs placebo

63
What does this all mean?
  • This is just a model.
  • Empirical evaluation of the population impact of
    mass vaccination programs is crucial to determine
    whether modelling predictions will occur, and to
    base policy for further vaccination should it be
    required.
  • Waiting 70 years for definitive evidence to fully
    evaluate these predictions must be traded off
    against the aggregate societal benefit of
    varicella prevention.
  • Must have good zoster surveillance.
  • If VZV vaccine is to be used, uptake must be
    achieved in a very high proportion of the
    non-immune population.

64
New vaccines
  • HPV (Human Papilloma Virus 6, 11, 16, 18
    cervical cancer, genital warts)
  • HSV (Herpes Simplex Virus neonatal herpes,
    genital herpes)
  • Rotavirus (gastroenteritis)
  • Intranasal influenza (Cold-adapted,
    heat-attenuated live virus)
  • PIV (Parainfluenza 1 and 3 croup)
  • HIV (AIDS)
  • MMR-V (MMR and varicella)
  • MenCY and other conj MenC combos
  • MenB
  • Also CMV, malaria, TB, chlamydia, GAS, GBS, EBV

65
HPV-16 vaccine efficacy
Koutsky et al. Efficacy analysis of an HPV-16 L1
virus-like-particle vaccine. NEJM
2002341645-51.
66
Coronavirus virion (Holmes KV. SARS-associated
coronavirus. NEJM 20033481948-51)
67
Conclusions
  • Must be vigilant, flexible and adaptable
  • Cost-effective health gain through vaccine
    prevention of disease still comes at a cost that
    governments with short funding cycles and
    sometimes short-sighted view of the future need
    to provide.
  • Healthcare providers need to adapt to these
    changes
  • Need to provide preventative healthcare
    frameworks that facilitate effective uptake of
    vaccines, especially adults and adolescents.
  • Vaccines offer some of the best value for health
    maintenance. Lets take advantage of it.

68
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