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Australia implemented conjugate meningococcal C immunization in 2003 with a single scheduled dose at age 12 months and catch-up for individuals aged 2-19 years. Several countries have recently added one or more booster doses to their programmes to maintain disease control. Australian disease surveillance and vaccine coverage data were used to assess longer term vaccine coverage and impact on invasive serogroup C disease incidence and mortality, and review vaccine failures. Coverage was 93% in 1-year-olds and 70% for catch-up cohorts. In 10 years, after adjusting for changes in diagnostic practices, population invasive serogroup C incidence declined 96% (95% confidence interval 94-98) to 0·4 and 0·6 cases/million in vaccinated and unvaccinated cohorts, respectively. Only three serogroup C deaths occurred in 2010-2012 vs. 68 in 2000-2002. Four (<1/million doses) confirmed vaccine failures were identified in 10 years with no increasing trend. Despite published evidence of waning antibody over time, an ongoing single dose of meningococcal C conjugate vaccine in the second year of life following widespread catch-up has resulted in near elimination of serogroup C disease in all age groups without evidence of vaccine failures in the first decade since introduction. Concurrently, serogroup B incidence declined independently by 55%.

The epidemiology of hepatitis A is changing, with an increasing proportion of the population becoming susceptible to infection. The burden of hepatitis A is comparable to that of other vaccine-preventable diseases for which new vaccines are available. Options for vaccination include selective programmes for high-risk groups, which could involve screening prior to vaccination, or universal programmes for infants and/or adolescents. Selective programmes have been shown to be highly cost-effective if well implemented, but there is evidence that they might be poorly implemented. If a universal vaccination programme were considered for Australia, an infant programme, with doses at 18 months and 2 years, possibly with an additional adolescent programme, would be the recommended option. Universal hepatitis A vaccination for infants and/or adolescents is of comparable cost-effectiveness compared with other preventive strategies, but needs to be considered in the context of competing vaccination options.

Background: The aims of this study were to determine the impact of the Australian Measles Control Campaign (MCC) on the transmission dynamics of measles by calculating the reproductive number (R) before and after the MCC, and to predict measles control in Australia in the future., Methods: A national serosurvey was conducted before and after the MCC. Sera were tested for anti-measles IgG using enzyme immunoassay (EIA). A mathematical model, using serosurvey results and vaccine coverage estimates, was used to calculate the change in R after the MCC., Results: The values of R calculated before and after the MCC were 0.90 and 0.57. At vaccine coverage levels indicated by the Australian Childhood Immunisation Register (ACIR), the value of R will exceed 1 (the epidemic threshold) in 2007-2008 nationally, and sooner in some regions of Australia. Coverage of at least 84% with two doses of MMR is required to sustain measles control., Conclusions: The Australian MCC had a significant impact on the transmission dynamics of measles. However, current vaccine coverage levels may result in indigenous measles transmission by 2007. Sustained efforts are required to improve coverage with two doses of MMR and to ensure elimination of indigenous measles transmission.

Objective: To evaluate the relationships between socio-economic and demographic variables and low immunisation coverage at the national level., Methods: The Australian Childhood Immunisation Register (ACIR) contains data at the postcode level on the immunisation status of all children registered with Medicare under the age of seven years. The Australian Bureau of Statistics (ABS) produces a number of indicators of socio-economic status at the postcode level from Census data. These and other ABS demographic data were used to examine the relationship between immunisation coverage and various socio-demographic indicators., Results: Factors associated with lower immunisation uptake differed in rural and metropolitan areas. High levels of education and occupation and a high proportion of Aboriginal residents were significantly associated with lower coverage only in metropolitan postcodes. High unemployment was associated with lower immunisation coverage only in rural postcodes. A high proportion of late starters to immunisation was the strongest single predictor of coverage and was important in rural and metropolitan postcodes. A high proportion of overseas-born persons and of GP-delivered immunisations was also associated with lower coverage in all areas., Conclusions: These data suggest that in metropolitan areas, reasons for low uptake in more advantaged areas require further evaluation. In non-metropolitan areas, low coverage was associated with areas of disadvantage, for which access to services may be more important., Implications: Children who are late in starting the schedule should be targeted.

The 1998 Australian Measles Control Campaign had as its aim improved immunization coverage among children aged 1-12 years and, in the longer term, prevention of measles epidemics. The campaign included mass school-based measles-mumps-rubella vaccination of children aged 5-12 years and a catch-up programme for preschool children. More than 1.33 million children aged 5-12 years were vaccinated at school: serological monitoring showed that 94% of such children were protected after the campaign, whereas only 84% had been protected previously. Among preschool children aged 1-3.5 years the corresponding levels of protection were 89% and 82%. During the six months following the campaign there was a marked reduction in the number of measles cases among children in targeted age groups.

The Australian Childhood Immunisation Register (ACIR) commenced operation in January 1996 and provides a comprehensive database of children's immunisations in Australia. The ACIR enables implementation of an immunisation recall and reminder system and improved surveillance and reporting of immunisation coverage. Before the introduction of the ACIR, the methods used in assessing coverage varied widely in design and quality, with few studies measuring coverage at national or statewide level. This is a systematic review of the scope and reliability of estimates of immunisation coverage available in Australia from 1990 to 1998. A total of 108 studies were identified of which 51 were classified as higher quality based on a range of criteria including whether they had a response rate of 50% or better.