Vaccine preventable diseases and vaccination coverage in Aboriginal and Torres Strait Islander people, Australia 2003 to 2006.

This, the second report on vaccine preventable diseases and vaccination coverage in Aboriginal and Torres Strait Islander people, brings together the relevant sources of routinely collected data on vaccine preventable diseases--notifications, hospitalisations, deaths, and childhood and adult vaccination coverage. As a result of continued improvements in the collection of data on Indigenous status, this second report is considerably more comprehensive, with data available from more jurisdictions, and more detailed presentation, including time trends and vaccination coverage by jurisdiction. Vaccination coverage data provide evidence of successful program delivery and highlight some areas for improvement. For universally funded vaccines in children, coverage is similar in Indigenous and non-Indigenous children by 24 months of age. However, delayed vaccination is more common in Indigenous children, with 6%-8% fewer children fully vaccinated at 12 months of age. More timely vaccination, particularly within the first six months of life, is particularly important in reducing the disproportionate burdens of disease due to pertussis and Haemophilus influenzae type b (Hib). For vaccination programs targeted specifically at Aboriginal and Torres Strait Islander children and adults, coverage is substantially lower than for those programs targeted at all Australians. This is true for hepatitis A and polysaccharide pneumococcal vaccine for children, and influenza and polysaccharide pneumococcal vaccine for adults. Targeted vaccination programs present a particular challenge for health services in urban areas. Nevertheless, the impact of vaccination programs in preventing disease and reducing the disparity of disease burden between Aboriginal and Torres Strait Islander and non-Indigenous people has been substantial. This is evident in data on notifications, hospitalisations and deaths. Diseases which, in the past, have had devastating and often disproportionately high impact on Indigenous people, such as diphtheria, measles, poliomyelitis, smallpox and tetanus, are now completely or almost completely absent from Australia. Hepatitis B infection, another disease responsible for high levels of infection and substantial serious illness and death in the pre-vaccine era, is also now well controlled in age groups eligible for vaccination. Although invasive Hib disease is now rare in Australia since the introduction of vaccination in 1993, higher rates of disease persist in Aboriginal and Torres Strait Islander children. More research is needed into the contribution of environmental factors, delayed vaccination and vaccine failure to this continued disparity. Hepatitis A has disproportionately affected Aboriginal and Torres Strait Islander children in the past. Vaccination programs in north Queensland and in various other countries have been very successful in reducing the burden of hepatitis A. It is too early to assess the impact of the vaccination program for Aboriginal and Torres Strait Islander children that commenced in regions outside north Queensland in November 2005. For some other diseases the situation is more complicated. The substantial impact of the national meningococcal C vaccination program since 2003 is evident in this report, although the higher proportion of non-vaccine preventable serotype B disease in Aboriginal and Torres Strait Islander people underlines the need for a new vaccine to cover this serotype. Pneumonia remains the most important communicable disease contributor to premature mortality in Aboriginal and Torres Strait Islander people of all ages. In young Indigenous adults, the eightfold higher rate of hospitalisation compared with their non-Indigenous peers, and the 11-fold higher rate of invasive pneumococcal disease, suggest the need for more widespread use of influenza and pneumococcal vaccines in this age group. Current coverage for Indigenous 15-49 year olds, where influenza and pneumococcal vaccines are funded only for those with risk factors, is low even though some 70% of this age group have one or more risk factors. Overall, the data presented in this report provide powerful evidence for the impact of vaccines in reducing disease in Aboriginal and Torres Strait Islander people, and also point to areas for further improvement. Immunisation programs are an example of how preventive health programs in general can be enhanced to close the gap in morbidity and mortality between Indigenous and non-Indigenous Australians.