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Publisher: Elsevier BV
Date: 10-2018
DOI: 10.1016/J.VACCINE.2018.08.084
Abstract: The Australian infant pneumococcal vaccination program was funded in 2005 using the 7-valent pneumococcal conjugate vaccine (PCV7) and the 13-valent conjugate vaccine (PCV13) in 2011. The PCV7 and PCV13 programs resulted in herd immunity effects across all age-groups, including older adults. Coincident with the introduction of the PCV7 program in 2005, 23-valent pneumococcal polysaccharide vaccine (PPV23) was funded for all Australian adults aged over 65 years. A multi-cohort Markov model with a cycle length of one year was developed to retrospectively evaluate the cost-effectiveness of the PPV23 immunisation program from 2005 to 2015. The analysis was performed from the healthcare system perspective with costs and quality-adjusted life years discounted at 5% annually. The incremental cost-effectiveness ratio (ICER) for PPV23 doses provided from 2005 to 2015 was calculated separately for each year when compared to no vaccination. Parameter uncertainty was explored using deterministic and probabilistic sensitivity analysis. It was estimated that PPV23 doses given out over the 11-year period from 2005 to 2015 prevented 771 hospitalisations and 99 deaths from invasive pneumococcal disease (IPD). However, the estimated IPD cases and deaths prevented by PPV23 declined by more than 50% over this period (e.g. from 12.9 deaths for doses given out in 2005 to 6.1 in 2015), likely driven by herd effects from infant PCV programs. The estimated ICER over the period 2005 to 2015 was approximately A$224,000/QALY gained compared to no vaccination. When examined per year, the ICER for each in idual year worsened from $140,000/QALY in 2005 to $238,000/QALY in 2011 to $286,000/QALY in 2015. The cost-effectiveness of the PPV23 program in older Australians was estimated to have worsened over time. It is unlikely to have been cost-effective, unless PPV23 provided protection against non-invasive pneumococcal pneumonia and/or a low vaccine price was negotiated. A key policy priority should be to review of the future use of PPV23 in Australia, which is likely to be more cost-effective in certain high-risk groups.
Publisher: MDPI AG
Date: 29-05-2019
Abstract: Background: Aboriginal Australian children have higher rates of mortality at younger ages than non-Aboriginal Australian children. We aimed to (i) calculate the case fatality rate (CFR) for Aboriginal and non-Aboriginal children admitted to children’s hospitals in New South Wales (NSW) and (ii) identify predictors of CFR. Methods: We used a retrospective cross-sectional analysis of data from electronic medical records for in-patient admissions to the Sydney Children’s Hospitals Network (SCHN) over five years (2011–2015). Logistic regression analysis was used to identify predictors of mortality and excess deaths in Aboriginal children were calculated. Results: There were 241,823 presentations over the 5-year period. The CFR for Aboriginal children was double that of non-Aboriginal children (0.4% vs. 0.2%, p = 0.002), with Aboriginal children under 2 years and from remote and regional Australia at highest risk of excess mortality. Predictors of death for all children in order of significance were: Circulatory disorders (Odds Ratio (OR) 17.16, p 0.001), neoplasm/blood/immune disorders (OR 2.77, p 0.001), emergency admissions (OR 1.94, p 0.001), aboriginality (OR 1.73, p = 0.005) and longer length of stay (OR 1.012 p 0.001). Conclusions: Our data show that Aboriginal children are almost twice as likely to die than non-Aboriginal children. In particular, excess deaths in Aboriginal children are most commonly from outer regional and remote areas and children aged under 2 years with perinatal or circulatory conditions.
Publisher: Future Medicine Ltd
Date: 06-2008
Abstract: Since the efficacy of pneumococcal conjugate vaccine (PCV) against invasive pneumococcal disease in young children was first demonstrated in clinical trials in California, USA, in the late 1990s, it has been studied in more erse populations and introduced into infant vaccination programs in the USA, Australia, Canada and several European countries. This review briefly describes the epidemiology of pneumococcal disease, recent literature on PCV trials in various study populations, the impact of 7-valent PCV infant vaccination on the epidemiology of invasive pneumococcal disease, with special reference to indirect effects in older age groups and the emergence of serotype replacement disease. Variations in vaccine administration schedules, effects on noninvasive pneumococcal diseases, and the use of the polysaccharide pneumococcal vaccine or future formulations of pneumococcal conjugate vaccines from the perspective of policy decisions for population-wide childhood pneumococcal vaccination programs are also highlighted.
Publisher: Elsevier BV
Date: 02-2018
DOI: 10.1016/J.VACCINE.2018.01.052
Abstract: While the impact of the timeliness of vaccine administration has been well-studied for childhood vaccinations, there has been little detailed quantitative analysis on the potential impact of the timeliness of vaccinations in older adults. The aim of this study was to explore the impact of implementing more realistic observed uptake distributions, taking into the account reduced vaccine efficacy but higher pneumococcal disease burden with increasing age beyond 65 years. A multi-cohort Markov model was constructed to evaluate the cost-effectiveness of a pneumococcal (PCV13) immunisation program in Australia, assuming two different uptake modelling approaches. The approach using an estimate of observed uptake was compared with a scenario in which the total cumulative uptake was delivered at the recommended age of vaccination. We found these two approaches produced different results both in terms of cases prevented and cost-effectiveness. The impact of the non-timely uptake in adult programs may sometimes have positive and other times negative effects, depending on several factors including the age-specific disease rates and the duration of vaccine protection. Our study highlights the importance of using realistic assumptions around uptake (including non-timely vaccination) when estimating the impact of vaccination in adults.
Publisher: Wiley
Date: 14-04-2015
DOI: 10.1111/JPC.12896
Abstract: Cytomegalovirus (CMV) is an important cause of congenital infection, which can result in neonatal deaths or contribute to deaths in later childhood. Post-natally acquired CMV is a less common cause of disease and mortality, and only in preterm infants or immunocompromised children. Here we sought to describe CMV as a direct or secondary contributor to childhood mortality in Australia. We searched national mortality data sets between1999 and 2011 for cases <15 years with CMV recorded as an underlying or contributing cause of death. Eighty-three CMV-associated deaths in children <15 years were identified (0.2 cases per 100 000 <15 years 95% confidence interval 0.16-0.24). Childhood deaths associated with CMV were evenly distributed between males and females, and the majority (n = 57 68%) occurred in children less than 12 months of age, with 22 cases <1 month of age. Over the 13-year study period, the mortality rate remained stable and CMV resulted in an estimated age-adjusted 5925 years of potential life lost. CMV makes a small but important contribution to childhood mortality in Australia. Most CMV-related deaths occurred in infants <12 months of age. These infant deaths may be an indirect marker of the burden of severe intrauterine CMV disease given the natural history of this infection.
Publisher: Elsevier BV
Date: 06-2012
DOI: 10.1016/J.VACCINE.2012.04.025
Abstract: This study evaluates the evidence for elimination of rubella and congenital rubella syndrome (CRS) in Australia, drawing on three national serosurveys conducted between 1996 and 2007 and supported by statutory notification and vaccine coverage data. Anti-rubella IgG seropositivity was defined as ≥ 10 IU/ml by EIA. Between 1998 and 2007, rubella notifications fell >100-fold, to an average of 2 cases per million and there were five confirmed cases of CRS, two of which were locally acquired in 2003. Weighted overall seropositivity remained constant among 1-49 year-olds (89.6% in 1999 88.1% in 2007). Between 2002 and 2009, 95% of children received at least one dose of the measles-mumps-rubella (MMR) vaccine. All three serosurveys provided estimates for R less than 0.5, well below the epidemic threshold of 1. All available data are supportive of Australia being considered for elimination status. Further reductions in incidence of CRS will require continued attention to vaccine coverage in overseas-born women, as well as the maintenance of current high coverage level of two-dose MMR vaccination.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2010
DOI: 10.1097/INF.0B013E3181D7D09C
Abstract: Postmarketing surveillance of heptavalent pneumococcal conjugate vaccine (7vPCV) has shown significant reductions in admissions coded as pneumonia in countries where a booster dose is given in the second year of life. In Australia, a 3-dose primary schedule at 2, 4, and 6 months of age without a booster has been funded nationally for non-Indigenous children since 2005. All hospital discharges in Australia with the primary diagnosis coded as pneumonia between July 1998 and June 2007 were identified from a national electronic database. Monthly rates of hospitalization for pneumonia over this period were determined for the age groups or = 65 years. Negative binomial regression modeling,adjusting for background and seasonal trends, was used to quantify the effect of the 7vPCV program. A total of 523,591 eligible hospital discharges were identified. In the 30 months following 7vPCV introduction, there were significant adjusted reductions in all-cause pneumonia in children aged < 2 and 2 to 4 years of 38%(95% CI 36%-40%), and 29% (26%-31%), respectively. Reductions of between 3% and 11% were observed in the older age groups. The significant differential effects observed are strongly suggestive of the PCV7 program being responsible for the observed reduction in pneumonia hospitalizations in Australia, and the magnitude was comparable to that documented in countries with a booster dose. This finding appears robust and may be related to high levels of vaccination coverage and catch-up early in the program, or to relatively lower levels of serotype replacement without a booster dose.
Publisher: Wiley
Date: 15-08-2005
DOI: 10.1111/J.1445-5994.2005.00909.X
Abstract: Acute epiglottitis due to infection with Haemophilus influenzae type b (Hib) is much less common in children following the introduction of Hib vaccination however, adult epiglottitis cases have not decreased. In addition, epiglottitis hospitalizations are consistently more numerous than notifications and the reason for this is not clear. To more accurately describe the clinical, aetiological and epidemiological features of epiglottitis and to ascertain the accuracy of hospitalization data in an era of widespread Hib vaccination. Medical records in 11 public hospitals in three area health services in New South Wales with a principal or stay diagnosis (International Classification of Diseases (ICD)-9-CM or ICD-10-AM code) of acute epiglottitis between July 1990 and June 1992 (prior to Hib vaccination = pre-vaccine era) and July 1998 and June 2000 (widespread Hib vaccination = vaccine era) were reviewed. Case definitions of epiglottitis were applied. One hundred and forty-two records were identified (114 pre-vaccine era and 28 vaccine era). Incorrect coding was more common in vaccine era records (32 vs 7%). Of correctly coded records, adults over 20 years old comprised the majority in the vaccine era (84 vs 17%). Hib bacteraemia was identified in 62% of cases in the pre-vaccine era compared to no cases in the vaccine era, despite equivalent blood cultures being taken between the two eras (84 vs 74%). Streptococcus pneumoniae was the only other organism isolated. Three deaths were recorded (1 child, 2 adults), all in the pre-vaccine era. Acute epiglottitis hospitalizations in the current Hib vaccine era are predominantly in adults, and rarely are Hib or other causative organisms identified, although microbiological data are often incomplete. The discrepancy between hospitalization and notification data appears to be due to misclassification of hospitalization records.
Publisher: Springer Science and Business Media LLC
Date: 20-06-2013
Publisher: Elsevier BV
Date: 2007
DOI: 10.1016/J.VACCINE.2006.08.022
Abstract: This ecological study aimed to identify possible reasons for higher pertussis hospitalization rates in indigenous Australian infants. Two national datasets were analysed: the Hospital Morbidity Database and the Australian Childhood Immunisation Register (ACIR). Most (52%) pertussis hospitalizations in indigenous infants occurred at 0-2 months of age, and rates in these indigenous infants were significantly higher in remote areas. Indigenous infants had higher hospitalization rates and more frequently delayed vaccination than non-indigenous infants of the same age. These data suggest that residence in a remote area, as a proxy for poorer living conditions for indigenous people, and delayed vaccination, both contribute to higher pertussis hospitalization rates in indigenous infants.
Publisher: Oxford University Press (OUP)
Date: 21-10-2016
DOI: 10.1093/CID/CIW720
Abstract: Australia introduced universal 7-valent pneumococcal conjugate vaccine (PCV7) from 2005, replaced by 13-valent PCV (PCV13) in 2011, uniquely among high-income countries giving doses at 2, 4, and 6 months (3 + 0 schedule). Data on impact of a timely 3 + 0 PCV schedule with high coverage are sparse, with none for PCV13. We used national surveillance of invasive pneumococcal disease (IPD) from 2002 for baseline and appropriate later comparison periods to calculate incidence rate ratios (IRRs) by serotype and age using a Poisson model. PCV coverage was assessed from the Australian Childhood Immunisation Register. After 9 years of timely 3-dose PCV coverage of >92%, all-age IPD in Australia almost halved (IRR, 0.53 95% confidence interval [CI], .50-.57), but differed by PCV era. Reductions in IPD due to vaccine serotypes from PCV7 (IRR, 0.20 CI, .17-.22) were about 2-fold greater than for IPD due to extra serotypes in PCV13 (13v-non7v) in a similar period (IRR, 0.58 CI, .51-.66). Post-PCV13 declines in serotype 19A IPD in persons aged <2 years (IRR, 0.23 CI, .13-.35) and ≥2 years (IRR, 0.35 CI, .28-.44) differed from other 13v-non7v IPD (IRR, 0.73 CI, .35-1.48 for those aged <2 years and IRR, 0.96 CI, .81-1.15 for those ≥2 years). Meningitis due to vaccine serotypes nearly disappeared in children eligible for 3 PCV13 doses. IPD due to non-PCV13 serotypes increased by 30% compared with 76% for non-PCV7 serotypes in equivalent period of vaccine use. Reductions in vaccine-type IPD post-PCV13 were inferior to Australian experience with PCV7 and reports from high-income countries giving a PCV booster dose. Applicability of findings to other settings would depend on age of IPD onset, serotype profile, and timeliness of vaccination.
Publisher: Oxford University Press (OUP)
Date: 11-06-2015
DOI: 10.1093/CID/CIV429
Abstract: Studies evaluating long-term trends in hospitalizations coded as pneumonia following introduction of the 7-valent pneumococcal vaccine (PCV7) are sparse, especially in adults. We extended our previous analysis to 6.5 years after the "3 + 0" PCV7 schedule was introduced in Australia in 2005. We estimated vaccine impact on hospitalizations coded as pneumonia (pneumococcal/lobar, other specified, unspecified, and all-cause) using a multivariate negative binomial regression model of monthly hospitalization rates by age group for the pre-PCV7 (July 1998 to December 2004) and post-PCV7 (January 2005 to June 2011) periods, adjusting for vaccination coverage. Changes in pneumonia hospitalizations were measured as incidence rate ratios. A total of 791 000 hospitalizations coded as pneumonia were identified unspecified causes accounted for >85%. Reductions in pneumonia coded as pneumococcal/lobar were statistically significant in all age groups and greatest in children. Significant reductions in all-cause pneumonia were seen only in children aged <2 years (32% 95% confidence interval [CI], 28%-37%) and 2-4 years (20% 95% CI, 14%-27%), with no significant changes in other age groups, including adults aged 65-74 (4% 95% CI, -3% to 10%), 75-84 (2% 95% CI, -4% to 9%), and ≥85 years (3% 95% CI, -3% to 10%). We could not replicate reductions of 23% in all-cause pneumonia 7-9 years post-PCV7 introduction reported for adults aged ≥85 years in the United States. This could be attributable to vaccine program factors, differing proportions of pneumonia due to pneumococci, or data limitations. More data from countries with differing PCV schedules and from the PCV13 era are needed to inform vaccination strategies for elderly adults.
Publisher: Springer Science and Business Media LLC
Date: 26-09-2016
DOI: 10.1186/S12879-016-1820-8
Abstract: In the absence of an adult vaccination register, coverage estimates for influenza and pneumococcal vaccination come from surveys and other data sources. Systematic review and meta-analysis of studies examining vaccination coverage in Australian adults from 1990 to 2015, focusing on groups funded under the National Immunisation Program, and intervals prior to and following the introduction of universal funding. Twenty-two studies met the inclusion criteria 18 used self-report to determine vaccination status. There were 130 unique estimates of coverage extracted. Among adults aged ≥65y, during the period of universal funding (1999-onwards), the summary estimate of annual influenza vaccination coverage from 27 point estimates was 74.8 % (95 % CI 73.4-76.2 % range 63.9-82.4 %) prior to this period (1992-1998) from 10 point estimates it was 61.3 % (95 % CI 58.0-64.6 % range 44.3-71.3 %). For the period of universal funding for pneumococcal vaccination (2005-onwards) the summary estimate for coverage was 56.0 % (95 % CI 53.2-58.8 % range 51.2-72.8 %, 10 point estimates) prior to 2005 it was 35.4 % (95 % CI 18.8-52.0 % range 15.4-45.2 %). Coverage for both vaccines was significantly higher following the introduction of universal funding. Influenza vaccination coverage in those aged 18-65 years with a medical indication was lower but data were not combined. Seven studies reported on Aboriginal Australians with three studies reporting five coverage estimates for influenza vaccination in adults ≥65 years (range 71 % - 89 %). Adult influenza and pneumococcal vaccination coverage has increased since the introduction of universal funding, but remains sub-optimal, with pneumococcal coverage lower than influenza. This review highlights the need for more coverage data overall and in high risk groups, to support public health programs to improve coverage.
Publisher: Elsevier BV
Date: 10-0005
DOI: 10.1016/J.VACCINE.2013.11.067
Abstract: Post-implementation evaluation should play an important role in assessing the success of public health programmes however, the value for money achieved by vaccine programmes after introduction has received relatively little attention to date. In this article we explore the methodological challenges in these analyses and offer direction for future evaluations in the area. We identify alternative approaches to addressing these challenges, which include the estimation of disease changes attributable to vaccination efforts, the hypothetical no vaccination comparator scenario and the full benefit achieved by implemented vaccination programmes. We also outline other important considerations such as the evolution of prices over time. Further work needs to be done to explore these issues and to determine how the application of different approaches may impact on the results of evaluations in various circumstances. As retrospective analyses are likely to become more frequent and influential, it is important that both the benefits and the limitations of post-implementation evaluations are recognised and understood. We argue that it would be useful to establish a methodological framework to provide standards and guidance on how to undertake such analyses in the future.
Publisher: Bentham Science Publishers Ltd.
Date: 31-10-2014
DOI: 10.2174/1871526514666140714084934
Abstract: This study examines national childhood HSV mortality data in Australia from 1999-2011. This information is important to better understand the disease burden of HSV in early life and to formulate public health interventions. Retrospective analysis of Australian Bureau of Statistics (ABS) national mortality data from 1999- 2011 in children aged <15 years who died with specific ICD-10 codes for HSV infection listed as an underlying or contributing cause. Twenty nine HSV-associated deaths in children aged <15 years from 1999-2011 were identified (0.05 per 100,000 children 95% CI 0.04-0.06), 16 in the first month of life (0.45 per 100,000 live births 95% CI 0.23- 0.67). Among those, 20 were males and 9 were females (p=0.04). The majority of deaths (69%) occurred in infants aged <12 months and most in infants aged <1 month (55%). HSV-associated death in infants aged < 1 month of age accounted for 0.15% of all neonatal deaths for 1999-2011 in Australia. A downward trend in HSV-associated neonatal mortality was observed between 1999 and 2011 (p=0.52). During the study period, mortality from HSV infections in Australian children resulted in an estimated 2,275 age-adjusted years of potential life lost. This data confirms reported findings from active surveillance of a downward trend in mortality rate from HSV infection in infants aged < 1 month in Australia over this period. Ongoing surveillance is required to confirm this observation.
Publisher: Elsevier BV
Date: 04-2013
DOI: 10.1016/J.VACCINE.2013.02.007
Abstract: Strict age limits for receipt of rotavirus vaccines and simultaneous use of vaccines requiring two (Rotarix(®)) and three (RotaTeq(®)) doses in Australia may impact on coverage and timeliness of other vaccines in the infant schedule. Using data from the Australian Childhood Immunisation Register (ACIR), coverage and timeliness of rotavirus vaccines and changes in timeliness of other infant vaccines following rotavirus vaccine introduction was examined, with particular emphasis on Indigenous infants in whom coverage is less optimal. Final dose rotavirus coverage reached 83% within 21 months of program commencement but remained 7% lower than other vaccines due in infancy. Coverage was 11-17% lower in Indigenous infants. Adherence to the first dose upper age limits for rotavirus vaccine was high with >97% of children vaccinated by the recommended age, but for subsequent rotavirus doses, receipt beyond the upper age limits was more common, especially in Indigenous children. Following rotavirus vaccine introduction, there were improvements in timeliness of receipt of all doses of DTPa-containing and 7-valent pneumococcal conjugate vaccines. High population coverage can be attained with rotavirus vaccines, even with adherence to strict upper age restrictions for vaccine dose administration. Rotavirus vaccine introduction appears to have impacted upon the timeliness of other concomitantly scheduled vaccines. These factors should be considered when rotavirus programs are introduced.
Publisher: Elsevier BV
Date: 11-2016
DOI: 10.1016/J.VACCINE.2016.09.039
Abstract: On the 20th June, 2014 the National Health and Medical Research Council's Centre for Research Excellence in Population Health "Immunisation in under Studied and Special Risk Populations", in collaboration with the Public Health Association of Australia, hosted a workshop "Equity in disease prevention: vaccines for the older adults". The workshop featured international and national speakers on ageing and vaccinology. The workshop was attended by health service providers, stakeholders in immunisation, ageing, primary care, researchers, government and non-government organisations, community representatives, and advocacy groups. The aims of the workshop were to: provide an update on the latest evidence around immunisation for the older adults address barriers for prevention of infection in the older adults and identify immunisation needs of these groups and provide recommendations to inform policy. There is a gap in immunisation coverage of funded vaccines between adults and infants. The workshop reviewed provider misconceptions, lack of Randomised Control Trials (RCT) and cost-effectiveness data in the frail elderly, loss of autonomy, value judgements and ageism in health care and the need for an adult vaccination register. Workshop recommendations included recognising the right of elderly people to prevention, the need for promotion in the community and amongst healthcare workers of the high burden of vaccine preventable diseases and the need to achieve high levels of vaccination coverage, in older adults and in health workers involved in their care. Research into new vaccine strategies for older adults which address poor coverage, provider attitudes and immunosenescence is a priority. A well designed national register for tracking vaccinations in older adults is a vital and basic requirement for a successful adult immunisation program. Eliminating financial barriers, by addressing inequities in the mechanisms for funding and subsidising vaccines for the older adults compared to those for children, is important to improve equity of access and vaccination coverage. Vaccination coverage rates should be included in quality indicators of care in residential aged care for older adults. Vaccination is key to healthy ageing, and there is a need to focus on reducing the immunisation gap between adults and children.
Publisher: Elsevier BV
Date: 03-2017
DOI: 10.1016/J.VACCINE.2017.01.063
Abstract: In early 2011, following an increased number of reports of severe vaccine-related injection site reactions, Australian authorities recommended against administering repeat doses of the 23-valent pneumococcal polysaccharide vaccine (23vPPV) in otherwise healthy adults. The aim of this study was to assess a source of electronic medical record data from primary care providers (General Practitioners, GPs), for validity and ability to retrospectively detect this adverse event signal. The General Practice Research Network (GPRN) holds data routinely collected from a representative s le of Australian GPs. Data were extracted on persons 18years or older who had received at least one dose of 23vPPV or influenza vaccine (as comparator) between January 2002 and June 2012. Increases above background levels were assessed using 95% confidence intervals of reaction rates, calculated from the Poisson distribution of counts. There was an average of 253 practices and 532 GPs contributing data per year. Over the study period there were 95,760 recorded 23vPPV administrations and 823 reactions, of which 233 were local. For influenza vaccine the numbers were 683,829 doses, 3001 and 387 respectively. Patterns of vaccinations and reactions were consistent with known safety profiles. There were 3 local reactions following 23vPPV in early 2011 (235/100,000 doses, 95% CI 49-717), which was not significantly different to the historical average (260, 225-298). We estimate that this system could have detected a 3-fold increase over background levels. Using GP consultation data, we were unable to confirm an increase in local reactions detected by passive surveillance, suggesting that this apparent signal was artefactual. GP consultation data captures large numbers of vaccine recipients and medically attended adverse reactions at low cost. If available in a timely manner and expanded, this system has significant potential for use in validation of apparent signals from passive surveillance.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2009
Publisher: Elsevier BV
Date: 04-2014
DOI: 10.1016/J.VACCINE.2014.02.044
Abstract: In 2010, use of seasonal trivalent influenza vaccine (TIV) in children 2 years) and region (Western Australia vs other Australian states/territories). A primary care consultation on the day after vaccine receipt is a reasonable proxy for early reactogenicity and has potential for use in various settings.
Publisher: Elsevier BV
Date: 02-2013
DOI: 10.1016/J.VACCINE.2012.12.052
Abstract: This paper examines how the monovalent varicella vaccine for children, with an adolescent catch-up dose, was introduced into Australia's National Immunisation Program (NIP), focusing on programme implementation. Semi-structured interviews were conducted with key informants involved in programme implementation. Key themes from interviews were identified through content analysis. Childhood coverage was assessed using data from the Australian Childhood Immunisation Register (ACIR) with adolescent coverage obtained from state/territory immunisation programmes. Seroprevalence data were analysed from national serosurveys conducted before and after programme commencement. Implementation challenges for both parents and providers included: (a) parental report of previous infection as an exclusion criterion (b) introducing a vaccine on its own at 18 months of age and (c) adding the adolescent dose into existing school-based vaccination programmes with parental reported exclusion criteria. Despite these challenges, coverage rapidly reached 83% by 24 months of age and 30-33% for the adolescent catch-up dose. When considered in conjunction with estimated pre-vaccination natural immunity in both target groups (20% and 83%, respectively) coverage can be considered high. The serosurvey under-estimated coverage in 2-year-old children but was useful to assess trends in population immunity. The introduction of a single dose of monovalent varicella vaccine at 18 months of age and a school-based catch-up programme at 11-13 years of age successfully achieved high coverage, notwithstanding some challenges. Reported natural infection has been an exclusion criterion for vaccination, but as the programme matures and circulation of wild-type virus decreases, the need for this warrants consideration. There is a need for sensitive laboratory assays to measure vaccine-induced immunity at a population level.
Publisher: The Sax Institute
Date: 2002
DOI: 10.1071/NB02024
Publisher: Elsevier BV
Date: 08-2017
DOI: 10.1016/J.VACCINE.2017.06.085
Abstract: The 23-valent pneumococcal polysaccharide vaccine (PPV23) has been funded under the Australia National Immunisation Program (NIP) since January 2005 for those aged >65years and other risk groups. In 2016, PCV13 was accepted by the Pharmaceutical Benefits Advisory Committee (PBAC) as a replacement for a single dose of PPV23 in older Australian adults. A single-cohort deterministic multi-compartment (Markov) model was developed describing the transition of the population between different invasive and non-invasive pneumococcal disease related health states. We applied a healthcare system perspective with costs (Australian dollars, A$) and health effects (measured in quality adjusted life-years, QALYs) attached to model states and discounted at 5% annually. We explored replacement of PPV23 with PCV13 at 65years as well as other age based vaccination strategies. Parameter uncertainty was explored using deterministic and probabilistic sensitivity analysis. In a single cohort, we estimated PCV13 vaccination at the age of 65years to cost ∼A$11,120,000 and prevent 39 hospitalisations and 6 deaths from invasive pneumococcal disease and 180 hospitalisations and 10 deaths from community acquired pneumonia. The PCV13 program had an incremental cost-effectiveness ratio of ∼A$88,100 per QALY gained when compared to a no-vaccination, whereas PPV23 was ∼A$297,200 per QALY gained. To fall under a cost-effectiveness threshold of A$60,000 per QALY, PCV13 would have to be priced below ∼A$46 per dose. The cost-effectiveness of PCV13 in comparison to PPV23 was ∼A$35,300 per QALY gained. In comparison to no-vaccination, we found PCV13 use in those aged 65years was unlikely to be cost-effective unless the vaccine price was below A$46 or a longer duration of protection can be established. However, we found that in comparison to the PPV23, vaccination with PCV13 was cost-effective. This partly reflects the poor value for money estimated for PPV23 use in Australia.
Publisher: Elsevier BV
Date: 11-2015
DOI: 10.1016/J.VACCINE.2015.10.089
Abstract: High incidence and serotype ersity of invasive pneumococcal disease (IPD) in Indigenous children in remote Australia led to rapid introduction of 7-valent conjugate pneumococcal vaccine (7vPCV) at 2, 4 and 6 months in 2001, followed by 23-valent polysaccharide pneumococcal vaccine (23vPPV) in the second year of life. All other Australian children were offered 3 doses of 7vPCV without a booster from 2005. This study evaluated the impact of the unique pneumococcal vaccine schedule of 7vPCV followed by the 23vPPV booster among Indigenous Australian children. Changes in IPD incidence derived from population-based passive laboratory surveillance in Indigenous children <5 years eligible for 23vPPV were compared to non-Indigenous eligible for 7vPCV only from the pre-vaccine introduction period (Indigenous 1994-2000 non-Indigenous 2002-2004) to the post-vaccine period (2008-2010 in both groups) using incidence rate ratios (IRRs) stratified by age into serotype groupings of vaccine (7v and 13vPCV and 23vPPV) and non-vaccine types. Vaccine coverage was assessed from the Australian Childhood Immunisation Register. At baseline, total IPD incidence per 100,000 was 216 (n=230) in Indigenous versus 55 (n=1993) in non-Indigenous children. In 2008-2010, IRRs for 7vPCV type IPD were 0.03 in both groups, but for 23v-non7v type IPD 1.2 (95% CI 0.8-1.8) in Indigenous versus 3.1 (95% CI 2.5-3.7) in non-Indigenous, difference driven primarily by serotype 19A IPD (IRR 0.6 in Indigenous versus 4.3 in non-Indigenous). For non-7vPCV type IPD overall, IRR was significantly higher in those age-eligible for 23vPPV booster compared to those younger, but in both age groups was lower than for non-Indigenous children. These ecologic data suggest a possible "serotype replacement sparing" effect of 23vPPV following 7vPCV priming, especially for serotype 19A with supportive evidence from other immunogenicity and carriage studies. Applicability post 10vPCV or 13v PCV priming in similar settings would depend on local serotype distribution of IPD.
Publisher: AMPCo
Date: 11-2017
DOI: 10.5694/MJA17.00677
Publisher: Elsevier BV
Date: 2017
DOI: 10.1016/J.VACCINE.2016.11.056
Abstract: Universal vaccination against rotavirus was included in the funded Australian National Immunisation Program in July 2007. Predictive cost-effectiveness models assessed the program before introduction. We conducted a retrospective economic evaluation of the Australian rotavirus program using national level post-implementation data on vaccine uptake, before-after measures of program impact and published estimates of excess intussusception cases. These data were used as inputs into a multi-cohort compartmental model which assigned cost and quality of life estimates to relevant health states, adopting a healthcare payer perspective. The primary outcome was discounted cost per quality adjusted life year gained, including or excluding unspecified acute gastroenteritis (AGE) hospitalisations. Relative to the baseline period (1997-2006), over the 6years (2007-2012) after implementation of the rotavirus program, we estimated that ∼77,000 hospitalisations (17,000 coded rotavirus and 60,000 unspecified AGE) and ∼3 deaths were prevented, compared with an estimated excess of 78 cases of intussusception. Approximately 90% of hospitalisations prevented were in children <5years, with evidence of herd protection in older age groups. The program was cost-saving when observed changes (declines) in both hospitalisations coded as rotavirus and as unspecified AGE were attributed to the rotavirus vaccine program. The adverse impact of estimated excess cases of intussusception was far outweighed by the benefits of the program. The inclusion of herd impact and declines in unspecified AGE hospitalisations resulted in the value for money achieved by the Australian rotavirus immunisation program being substantially greater than predicted bypre-implementation models, despite the potential increased cases of intussusception. This Australian experience is likely to be relevant to high-income countries yet to implement rotavirus vaccination programs.
Publisher: Wiley
Date: 12-05-2011
DOI: 10.1111/J.1440-1754.2011.02079.X
Abstract: Vaccination has provided major benefits to the health of indigenous children in the face of continuing poorer socioeconomic conditions but several issues have been identified for improvement. While indigenous children are vaccinated at high rates for the standard schedule vaccines, vaccination is more commonly delayed. Coverage for 'targeted' vaccines is substantially lower, and data on coverage for indigenous adolescents is non-existent. Improved identification of indigenous clients by immunisation providers and the expansion of the childhood register are required. The progressive removal of early-acting Haemophilus influenzae type b vaccines from schedules for indigenous children because of an international shortage raises the risk of disease re-emergence and highlights the need for vigilant surveillance including carriage. The expanded use of existing vaccines (influenza) and early adoption of new vaccines (higher valency pneumococcal conjugates) are needed to maximise benefits, in particular the potential to impact on non-invasive disease such as otitis media and non-bacteraemic pneumonia that are so prevalent in indigenous children.
Publisher: Elsevier BV
Date: 10-2007
Publisher: AMPCo
Date: 04-2017
DOI: 10.5694/MJA16.00811
Publisher: Wiley
Date: 05-2007
DOI: 10.1111/J.1440-1754.2007.01084.X
Abstract: To describe the epidemiology of hepatitis A in Indigenous Australian children. Analysis and mapping of national notification and hospitalisation data. Indigenous Australian children are at far higher risk of clinical hepatitis A than their non-Indigenous counterparts, particularly in the age group 0-4 years. Rates of hospitalisation (15.5 vs. 0.3 per 100,000) and notification (24.4 vs. 1.8 per 100,000) were higher in Indigenous children aged 0-4 years compared with other children in the same age group. In the age group 5-14 years, the rates were 4.4 per 100,000 (Indigenous) versus 0.6 per 100,000 (non-Indigenous) hospitalisations. This excess morbidity falls sharply with age. Rates were the highest in the Northern Territory, South Australia, Western Australia and North Queensland. Indigenous children are at risk of hepatitis A, particularly early in life. Mapping shows that rates were the highest in jurisdictions with the largest Indigenous populations. This study presents baseline data against which to measure the success of new hepatitis A vaccination programme for Indigenous Australian children which commenced in 2005.
Publisher: Cambridge University Press (CUP)
Date: 03-03-2015
Publisher: AMPCo
Date: 11-2017
DOI: 10.5694/MJA16.01102
Abstract: To evaluate trends in the proportion and severity of community-acquired pneumonia (CAP) attributable to Streptococcus pneumoniae (pneumococcus) in Australians aged 18 years and over. Systematic review with unpublished data from the largest study. Multiple key bibliographic databases to June 2016. Australian studies on the aetiology of CAP in adults. In the 12 studies identified, pneumococcus was the most common cause of CAP. Four studies were assessed as being of good quality. Participants in two studies were predominantly non-Indigenous (n = 991) the proportion of pneumococcal CAP cases declined from 26.4% in 1987-88 to 13.9% in 2004-06, and the proportion with bacteraemia decreased from 7.8% to 3.8%. In two studies with predominantly Indigenous participants (n = 252), the proportion with pneumococcal bacteraemia declined from 6.8% in 1999-2000 to 4.2% in 2006-07. In the largest study (n = 885 2004-06), 50.8% (60/118) of pneumococcal CAP occurred in people who were ≥ 65 years old. Among patients aged ≥ 65 years, intensive care unit admission and death were more common in patients who were ≥ 85 years old compared with younger patients (12.5% v 6.8% 18.8% v 6.8% respectively), and also more common in the 19 patients with bacteraemia than in those without it (15.8% v 2.6% 10.5% v 7.9% respectively). Of 17 cases of bacteraemia serotyped, 12 were due to 13-valent pneumococcal conjugate vaccine (13vPCV) serotypes and three to additional serotypes in 23-valent pneumococcal polysaccharide vaccine (23vPPV). Available data suggest that the proportion of CAP attributable to pneumococcus (both bacteraemic and non-bacteraemic) has been declining in Australian adults. Should 13vPCV replace the 23vPPV currently funded by the National Immunisation Program for persons aged ≥ 65 years, surveillance to track non-bacteraemic pneumococcal CAP will be essential to evaluate the impact.
Publisher: AMPCo
Date: 08-2014
DOI: 10.5694/MJA14.00399
Publisher: Elsevier BV
Date: 10-2019
DOI: 10.1016/J.VACCINE.2019.09.025
Abstract: Immunisation programs available in low and middle-income countries include fewer vaccines in comparison to Australia's National Immunisation Program. As a result, refugees and migrants may have a heightened risk of being inadequately immunised upon arrival to Australia. Several studies have suggested that East African immigrants have low vaccination coverage. As such, the aim of this study was to explore the underlying attitudes, barriers and facilitators to immunisation in east African communities in two states of Australia: New South Wales and Victoria. A qualitative study involving 17 semi-structured, in-depth interviews were undertaken with East African refugees and migrants living in two states of Australia: New South Wales and Victoria. These refugees and migrants were from four key East African countries: Kenya, Somalia, Ethiopia and South Sudan. Thematic analysis was undertaken to analyse and interpret the results. Language barriers, low risk perception and a lack of education were the key barriers identified by participants. Facilitators mentioned included the development of resources in participants' languages and the implementation of reminder systems consistently across all GP practices. There was also a unanimous agreement amongst participants that community organisations need to play a greater role in the dissemination of information about immunisation. Further research needs to be undertaken with regards to how education about immunisation is delivered and disseminated to refugee and migrant communities. Current findings also support the need to improve the health literacy of refugees and migrants by providing culturally and linguistically appropriate resources in participants' respective languages.
Publisher: Wiley
Date: 21-10-2003
DOI: 10.1046/J.1440-1754.2003.00244.X
Abstract: To evaluate the diagnostic pathways for whooping cough in a large urban paediatric hospital to inform assessment of the relative merits of notification and hospitalization data for measuring pertussis disease burden in Australian children. All laboratory requests for Bordetella pertussis (BP) culture or serology between 30 June 1997 and 30 June 1999 were reviewed and cross-checked against discharge diagnoses with International Classification of Disease (ICD) codes A37.0, 033.0 (whooping cough due to BP) or 37.9, 033.9 (whooping cough due to unspecified organisms). Culture-positive (CP) cases were defined as a positive culture or polymerase chain reaction for BP. Culture-negative (CN) cases either fulfilled the current Australian clinical case definition (>/=14 days of cough with one or more of paroxysms, whoop, post-tussive vomiting), or had a cough illness with either positive BP serology or documented contact with an in idual coughing for >14 days. In infants <6-months-old, a coughing illness with apnoea and negative investigations for other causes was also accepted. Culture positive and CN cases were cross-referenced with notification data. During the study period, laboratory tests for BP were performed in 677 children, of whom 230 were hospitalized and 71 (31%) had an eligible ICD code at discharge 29 were CP, 40 CN, and two (3%) were misclassified. A further 14 CP children were not admitted. Although 61 hospitalized cases (88%) fulfilled notification criteria, including 32 (80%) of CN cases, only 26 (90%) of CP and eight (20%) of CN cases were notified. Notifications substantially under-enumerate hospitalized infant cases, especially those without positive laboratory tests. Hospital discharge data add significantly to surveillance for pertussis, particularly in infancy where most severe cases occur.
Publisher: Oxford University Press (OUP)
Date: 06-2006
Abstract: Compared with nonindigenous people, indigenous people in first-world countries have experienced much higher rates of many vaccine preventable diseases. This systematic review of published scientific literature, government reports, and immunization guidelines from Australia, Canada, New Zealand, and the United States compares pre- and postvaccination disease rates and vaccination policy for indigenous people in these four countries. Nationally funded universal vaccination programs are clearly the most effective way of reducing disease in indigenous populations. Most successful have been programs for viral diseases in which strain variations are not important and herd immunity is high, such as measles and hepatitis B. For bacterial infections, strain variations (pneumococcal disease), heavy nasopharyngeal colonization of young infants (pneumococcal and Haemophilus influenzae type b disease), low vaccine effectiveness in adults with a high prevalence of risk factors (polysaccharide pneumococcal vaccine), and waning immunity (pertussis) have been associated with continuing or widening disparities between indigenous and nonindigenous populations. However, universal vaccination programs are not always possible. Geographic targeting of all persons in certain regions with high disease rates has been successful, as has targeting of indigenous populations in regions where they constitute larger proportions of the population. In national programs targeting only indigenous people, it has been difficult to achieve high coverage, particularly in urban areas. Innovative program approaches are particularly needed in these situations.
Publisher: Oxford University Press (OUP)
Date: 12-08-2014
Abstract: Human papillomavirus (HPV) vaccination targeting females aged 12-13 years commenced in Australia in 2007, with catch-up vaccination of females aged 13-26 years continuing to 2009. Whole-population analyses, including effects on the Indigenous population, have not previously been reported. All hospital admissions between 1999-2011 involving a diagnosis of genital warts were obtained from a comprehensive national database. We compared the age-specific rates before to those after implementation of the vaccination program, according to sex and other characteristics. Admission rates decreased from mid-2007 in females aged 12-17 years (annual decline, 44.1% [95% confidence interval {CI}, 35.4%-51.6%]) and from mid-2008 in females and males aged 18-26 years (annual declines, 31.8% [95% CI, 28.4%-35.2%] and 14.0% [95% CI, 5.1%-22.1%], respectively). The overall reductions from 2006-2007 to 2010-2011 were 89.9% (95% CI, 84.4%-93.4%) for females aged 12-17 years, 72.7% (95% CI, 67.0%-77.5%) for females aged 18-26 years, and 38.3% (95% CI, 27.7%-47.2%) for males aged 18-26 years. Compared with the average annual number before program implementation, about 1000 fewer hospital admissions involved a warts diagnosis during 2010-2011. Reductions after program implementation were similar for Indigenous (86.7% [95% CI, 76.0-92.7]) and non-Indigenous (76.1% [95% CI, 71.6%-79.9%]) females aged 15-24 years (P(heterogeneity) = .08). National population-based hospital data confirm previous clinic-based reports of a marked decline in genital warts diagnoses among young people in Australia after program implementation, including indirect benefits to males. The impact of HPV vaccination appears to be similar in young Indigenous and non-Indigenous females.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2009
Publisher: Wiley
Date: 10-1993
DOI: 10.1111/J.1476-5381.1993.TB13886.X
Abstract: 1. Renal function was studied in chronically catheterized fetal sheep (119-128 days gestation), before and during treatment of the ewe with the angiotensin converting enzyme (ACE) inhibitor, captopril, which crosses the placenta and blocks the fetal renin angiotensin system. 2. An i.v. dose of 15 mg (about 319 micrograms kg-1) of captopril to salt-replete ewes followed by an infusion to the ewe of 6 mg h-1 (about 128 micrograms kg-1 h-1) caused a fall in fetal arterial pressure (P < 0.01), and a rise in fetal renal blood flow (RBF) from 67.9 +/- 5.6 to 84.9 +/- 8.3 ml min-1 (mean +/- s.e. mean) (P < 0.05). Renal vascular resistance and glomerular filtration rate (GFR) fell (P < 0.01) fetal urine flow (P < 0.01) fetal urine flow (P < 0.01) and sodium excretion declined (P < 0.05). 3. Ewes were treated for the next 2 days with 15 mg captopril twice daily. On the 4th day, 15 mg was given to the ewe and fetal renal function studied for 2 h during the infusion of captopril (6 mg h-1) to the ewe. Of the 9 surviving fetuses, 3 were anuric and 3 had low urine flow rates. When 6 micrograms kg-1 h-1 of angiotensin II was infused directly into the fetus RBF fell from 69 +/- 10.1 ml min-1 to 31 +/- 13.9 ml min-1, GFR rose (P < 0.05) and urine flow (P < 0.01) and sodium excretion increased in all fetuses. 4. It is concluded that the small fall in fetal arterial pressure partly contributed to the fall in fetal GFR but in addition, efferent arteriolar tone fell so that the filtration pressure fell further. Thus maintenance of fetal renal function depends on the integrity of the fetal renin angiotensin system. These findings explain why use of ACE inhibitors in human pregnancy is associated with neonatal anuria.
Publisher: Oxford University Press (OUP)
Date: 17-02-2018
DOI: 10.1093/CID/CIY129
Abstract: Unique among high-income countries, Australia has used a 3 + 0 schedule (3 primary doses, no booster) for infant pneumococcal conjugate vaccine (PCV) since January 2005, initially 7 valent (PCV7) then 13 valent (PCV13) from July 2011. We measured vaccine effectiveness (VE) of both PCVs against invasive pneumococcal disease (IPD) using 2 methods. Cases were IPD notifications to the national surveillance system of children eligible for respective PCVs. For case-control method, up to 10 age-matched controls were derived from the Australian Childhood Immunisation Register. For indirect cohort method, controls were IPD cases due to serotypes not in PCVs. VE was calculated as (1 - odds ratio [OR]) × 100 by logistic regression. VE waning was estimated as odds of vaccine type (VT) IPD in consecutive 12-month periods post-dose 3. Between 2005 and 2014, there were 1209 and 308 IPD cases in PCV7-eligible and PCV13-eligible cohorts, respectively. Both methods gave comparable VE estimates. In infants, VE for 3 doses against VT IPD was 92.9% (95% confidence interval [CI], 27.7% to 99.3%) for PCV7 and 86.5% (95% CI, 11.7% to 97.9%) for PCV13. From 12 months post-dose 3, the odds of VT IPD by 24-36 months increased significantly for PCV7 (5.6, 95% CI, 1.2-25.4) and PCV13 (5.9, 95% CI, 1.0-35.2). For both PCVs in a 3 + 0 schedule, despite similar VE, progressive increase in breakthrough cases only occurred post-PCV13. This supports the importance of a booster dose of PCV13 in the second year of life to maintain protection.
Publisher: Informa UK Limited
Date: 31-01-2013
Publisher: AMPCo
Date: 10-2012
DOI: 10.5694/MJA12.10062
Abstract: To evaluate the impact of the Australian rotavirus vaccination program on both rotavirus and all-cause acute gastroenteritis (AGE) hospitalisations and to compare outcomes in Indigenous and non-Indigenous people. Retrospective analysis of the Australian Institute of Health and Welfare National Hospital Morbidity database for hospitalisations coded as rotavirus and all-cause AGE, between 1 July 2001 and 30 June 2010. Age-specific hospitalisation rates in Indigenous and non-Indigenous people, before and after the introduction of the vaccine program in July 2007. There was a 71% decline in rotavirus-coded hospitalisations of children aged < 5 years between periods before and after rotavirus vaccination (from 261 per 100,000 to 75 per 100,000). There was also a 38% decline in non-rotavirus coded AGE hospitalisations (from 1419 per 100,000 to 880 per 100,000). This represented more than 7700 hospitalisations of children aged < 5 years being averted in the financial year 2009-10. Reductions were also observed in the 5-19-years age group, suggesting that transmission of virus was reduced at a population level. Decreases in hospitalisations of Indigenous children were smaller than those for the general population, and fluctuated by location and year. These data show a sustained and substantial decline in severe rotavirus disease and all-cause AGE since the introduction of rotavirus vaccination, most pronounced in the target age group, but with evidence of herd immunity. The impact of rotavirus vaccination in Indigenous children in hyperendemic settings was less remarkable.
Publisher: Elsevier BV
Date: 2013
DOI: 10.1016/J.VACCINE.2012.11.043
Abstract: We investigated the impact of vaccination on rubella epidemiology in Australia, using a mathematical model fitted to Australian serosurvey data and incorporating pre-vaccination European estimates of rubella transmissibility. Mass infant measles-mumps-rubella (MMR) vaccination produced a 99% reduction in both rubella and congenital rubella syndrome (CRS) incidence by 2010 compared to the pre-vaccination era (1960-70). The model is consistent with reductions in CRS based on surveillance of congenital hearing impairment. Model simulations suggest that selective schoolgirl vaccination (1971-88) was associated with a 90% reduction in CRS incidence, but only a 1-4% reduction in rubella incidence. Our model predicted that these reductions in rubella were much less vulnerable to reductions in MMR vaccine coverage than for measles. In the future, a less than 15% decrease in MMR vaccine coverage is estimated to have minimal impact before 2060, but a 20% reduction may result in a 7-fold increase in rubella incidence, with the effective reproductive number R rising from 0.28 to 0.78 by 2060. The 99% reduction in both rubella and CRS incidence and low effective reproductive number (R≤0.28) we documented after 2010 are consistent with Australia having achieved rubella elimination.
Publisher: Cambridge University Press (CUP)
Date: 15-09-2014
DOI: 10.1017/S0950268814002222
Abstract: In Australia, varicella vaccine was universally funded in late 2005 as a single dose at 18 months. A school-based catch-up programme for children aged 10–13 years without a history of infection or vaccination was funded until 2015, when those eligible for universal infant vaccination would have reached the age of high school entry. This study projects the impact of discontinuing catch-up vaccination on varicella and zoster incidence and morbidity using a transmission dynamic model, in comparison with alternative policy options, including two-dose strategies. At current vaccine coverage (83% at 2 years and 90% at 5 years), ceasing the adolescent catch-up programme in 2015 was projected to increase varicella-associated morbidity between 2035 and 2050 by 39%. Although two-dose infant programmes had the lowest estimated varicella morbidity, the incremental benefit from the second dose fell by 70% if first dose coverage increased from 83% to 95% by age 24 months. Overall zoster morbidity was predicted to rise after vaccination, but differences between strategies were small. Our results suggest that feasibility of one-dose coverage approaching 95% is an important consideration in estimating incremental benefit from a second dose of varicella vaccine.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 06-2015
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2014
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2015
Publisher: AMPCo
Date: 02-2014
DOI: 10.5694/MJA12.11759
Abstract: To evaluate the impact and effectiveness of the 23-valent polysaccharide pneumococcal vaccine (23vPPV) in ≥ 65-year-old Australians in the context of concurrent 7-valent pneumococcal conjugate vaccine (7vPCV) use in infants. Ecological analysis of trends in invasive pneumococcal disease (IPD) notification rates and vaccine effectiveness estimation using the screening method, using data on Australians aged ≥ 65 years (23vPPV funded) and 50-64 years (23vPPV not funded). National 23vPPV program for people aged ≥ 65 years and national 7vPCV program for infants, both commencing in 2005. IPD incidence rate ratios, 2002-2004 to 2010-2011, and 23vPPV effectiveness against 23vPPV-type IPD. The proportion of people aged ≥ 65 years who were vaccinated within the previous 5 years in jurisdictions excluding Victoria ranged from 41% to 64% over the study period, with no clear trend over time. Incidence rate ratios in the ≥ 65-year age group were 0.11 (95% CI, 0.09-0.14) for 7vPCV serotypes, 1.64 (95% CI, 1.41-1.91) for 23vPPV-non-7vPCV serotypes and 2.07 (95% CI, 1.67-2.57) for non-23vPPV serotypes. The incidence rate ratio for total IPD was 0.65 (95% CI, 0.59-0.71) for people aged ≥ 65 years, and 0.80 (0.71-0.90) for people aged 50-64 years. The estimate of 23vPPV effectiveness was 61.1% (95% CI, 55.1%-66.9%). The greater reduction in IPD among ≥ 65-year-olds compared with 50-64-year-olds did not reach statistical significance. However, vaccine effectiveness was significant. Greater reductions in IPD in ≥ 65-year-olds would be expected from the indirect effects of using 13-valent pneumococcal conjugate vaccine in infants (introduced for Australian infants in 2011) and an increase in 23vPPV coverage.
Publisher: Elsevier BV
Date: 03-2020
Publisher: Elsevier BV
Date: 02-2015
DOI: 10.1016/J.VACCINE.2014.12.071
Abstract: Australia has achieved measles elimination as announced in March 2014 by the WHO Western Pacific Regional Committee, based on several lines of evidence. However, despite strong national evidence for elimination, there remains substantial regional variation in vaccine coverage, has resulted in recent outbreaks and potential for increased frequency in the future. In this study, we apply a multiple cohort model of measles immunity, stratified by age and local geographic area to predict trends in the measles reproduction number R. In addition, we use branching process models of outbreak risks to predict state-level probabilities of the occurrence of measles outbreaks over the next 20 years. Our results suggest increasing risks of large measles outbreaks over this period, in particular in the states of Queensland and New South Wales. In addition, there is wide variation in predicted R values by smaller geographic areas, although uncertainty in age-specific immunity limits the precision of our results. Our predictions align with observed outbreaks in Australian states and suggest our approach to determining future outbreak risks could be applied more widely in elimination or near-elimination settings.
Publisher: Springer Science and Business Media LLC
Date: 18-03-2015
Publisher: Elsevier BV
Date: 02-2007
DOI: 10.1111/J.1753-6405.2007.00013.X
Abstract: To obtain, through a survey, estimates of immunisation coverage in a birth cohort of Indigenous children, and to compare survey estimates with those obtained from the Australian Childhood Immunisation Register (ACIR) for the same birth cohort of Indigenous children. Cluster s ling of a birth cohort of two-year-old Indigenous children across Queensland, stratified according to accessibility/remoteness from services, was undertaken in 2003. An innovative method of identifying participants was used. Survey results of 10 vaccine doses were compared with ACIR data. The survey obtained a 4% s le of the birth cohort (137 children). Universally recommended vaccines showed high levels of coverage at 12 and 24 months, and survey estimates were slightly higher than ACIR estimates. Diphtheria-tetanus-acellular pertussis vaccine dose 3 (DTPa3) coverage was 93.8% (95% CI 88.0-99.6) by 12 months on survey and 87.5% on ACIR. Coverage was not timely and a lag phase of 4-6 months occurred for each vaccine dose. Haemophilus influenzae type b vaccine dose 2 (Hib2), scheduled for the age of four months, reached 90% coverage by nine months of age in the survey children. Both methods reported here provided similar results. These data indicate that ACIR Indigenous reporting rates have increased and coverage estimates are comparable to those provided by a survey. Immunisation coverage appears to be high, and the main remaining challenge in further reducing vaccine-preventable disease in Indigenous children is to improve immunisation timeliness.
Publisher: Elsevier BV
Date: 07-2021
Publisher: Informa UK Limited
Date: 17-01-2020
Publisher: Elsevier BV
Date: 12-2009
DOI: 10.1016/J.PCL.2009.09.006
Abstract: There are many similarities regarding the health status of Indigenous people in the 4 English-speaking developed countries of North America and the Pacific (United States, Canada, Australia, New Zealand), where they are all now minority populations. Although vaccines have contributed to the reduction or elimination of disease disparities for many infections, Indigenous people continue to have higher morbidity and mortality from many chronic and infectious diseases compared with the general populations in their countries. This review summarizes the available data on the epidemiology of vaccine-preventable diseases in Indigenous populations in these 4 countries in the context of the vaccination strategies used and their impact, with the aim of identifying successful strategies with the potential for wider implementation.
Publisher: Oxford University Press (OUP)
Date: 15-01-2006
DOI: 10.1086/498897
Abstract: Increases in incidence of invasive pneumococcal disease (IPD) during the colder months of the year in temperate regions are well recognized, but few detailed studies of possible interactions are available. We examined the relationship between virus activity, climatic parameters, and IPD during a winter in which there were separate peak incidences of influenza and respiratory syncytial virus (RSV) infection. We performed an ecological study that correlated population-based data on IPD and respiratory virus activity in the year 2000 in metropolitan New South Wales, Australia, with climatic parameters, including weekly mean maximum and minimum temperature, relative humidity, rainfall, and wind speed. In children, RSV activity was significantly positively correlated with IPD activity (r = 0.578 P = .002) but not with influenza virus activity. There was a weak inverse relationship between parainfluenza virus activity and IPD activity (r = -0.401 P = .043) and a stronger inverse relationship between weekly mean maximum temperature (r = -0.458 P = .001), weekly mean minimum temperature (r = -0.437 P = .001), and IPD activity. In adults, there was no significant correlation between RSV or influenza virus activity alone and IPD, but the combination of RSV and influenza was significantly correlated with IPD (r = 0.481 P = .013). This study suggests that RSV infection and influenza contribute to IPD incidence peaks differently for children than for adults. Data from other geographic areas and more rigorous study designs are required to confirm these findings.
Publisher: Elsevier BV
Date: 2016
DOI: 10.1016/J.VACCINE.2015.11.053
Abstract: Retrospective cost-effectiveness analyses of vaccination programs using routinely collected post-implementation data are sparse by comparison with pre-program analyses. We performed a retrospective economic evaluation of the childhood 7-valent pneumococcal conjugate vaccine (PCV7) program in Australia. We developed a deterministic multi-compartment model that describes health states related to invasive and non-invasive pneumococcal disease. Costs (Australian dollars, A$) and health effects (quality-adjusted life years, QALYs) were attached to model states. The perspective for costs was that of the healthcare system and government. Where possible, we used observed changes in the disease rates from national surveillance and healthcare databases to estimate the impact of the PCV7 program (2005-2010). We stratified our cost-effectiveness results into alternative scenarios which differed by the outcome states included. Parameter uncertainty was explored using probabilistic sensitivity analysis. The PCV7 program was estimated to have prevented ∼5900 hospitalisations and ∼160 deaths from invasive pneumococcal disease (IPD). Approximately half of these were prevented in adults via herd protection. The incremental cost-effectiveness ratio was ∼A$161,000 per QALY gained when including only IPD-related outcomes. The cost-effectiveness of PCV7 remained in the range A$88,000-$122,000 when changes in various non-invasive disease states were included. The inclusion of observed changes in adult non-invasive pneumonia deaths substantially improved cost-effectiveness (∼A$9000 per QALY gained). Using the initial vaccine price negotiated for Australia, the PCV7 program was unlikely to have been cost-effective (at conventional thresholds) unless observed reductions in non-invasive pneumonia deaths in the elderly are attributed to it. Further analyses are required to explore this finding, which has significant implications for the incremental benefit achievable by adult PCV programs.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 04-2002
DOI: 10.1097/00126334-200204010-00010
Abstract: To determine the effect of highly active antiretroviral therapy (HAART) on incidence of initial AIDS-defining illnesses (ADIs) and survival after in idual ADIs. Australian AIDS notification data over the period 1993 to 2000 were examined. Analyses were based on all initial ADIs. To examine the impact of HAART, two periods of AIDS diagnosis were chosen: pre-HAART (1993-1995) and HAART (1996-2000). Comparisons between these two periods included proportion of in idual ADIs, median CD4 lymphocyte counts at and survival following AIDS and in idual ADIs. Median survival was based on Kaplan-Meier estimates, with examination of factors influencing survival in a Cox proportional hazards model. Over the period 1993 to 2000 in Australia, 5017 initial ADIs were diagnosed among 4351 AIDS cases. At AIDS diagnosis, changes from the pre-HAART (1993-1995) to HAART (1996-2000) periods included an increased proportion of Pneumocystis carinii pneumonia (PCP) (25.9% to 30.4% p =.001), AIDS dementia complex (5.2% to 6.8% p = 0.029), non-Hodgkin lymphoma (NHL) (4.4% to 6.3% p =.005), and tuberculosis (0.5% to 2.7% p <.0005). Median survival following AIDS increased from 19.6 months for AIDS cases diagnosed in 1993 to 1995 to 39.6 months for AIDS cases diagnosed in 1996 to 2000 (p <.0005). Median survival was stable for NHL (7.5-8.8 months p =.26), but increased significantly for almost all other ADIs. An increased proportion of PCP relative to other ADIs suggests an increasing proportion of AIDS patients not receiving specific prophylaxis, presumably because of "late" HIV diagnosis. Survival following almost all ADIs has increased in the era of HAART, although the prognosis after NHL remains extremely poor.
Publisher: Springer Science and Business Media LLC
Date: 12-2015
Publisher: Elsevier BV
Date: 03-2021
Location: Australia
No related grants have been discovered for Rob Menzies.