Skip to content
|City||Adelaide, South Australia|
|University||University of Adelaide|
|Thesis type||Master of Public Health|
A survey, of all episodes of invasive H.influenzae disease that occurred over a three-year period in children in the Northern Territory and Central Australia, was conducted.
The survey documented a significantly higher incidence in Central Australia (the Alice Springs and Barkly regions, and the Anangu Pitjantjatjara Lands) than in the Top End (the Darwin, East Arnhem and Katherine regions), and a greater incidence in Aboriginal than in non-Aboriginal children. In particular, the Aboriginal children of Central Australia had an exceedingly high annual incidence of invasive H.influenzae disease, with a point estimate of 991 cases / 100,000 Aboriginal children less than five years of age. Identified risk factors for Aboriginal children were residence in Central Australia, infancy (over 70% of cases occurred before 12 months of age) and gender (with a predominance of cases occurring in girls); although not specifically studied in the survey it is likely that environmental crowding was also a major risk factor.
Whereas virtually all cases of invasive H.influenzae disease in non-Aboriginal children were caused by type b strains, strains other than type b caused 15% of the cases of disease in Aboriginal children. In this respect the epidemiology of invasive H.influenzae disease in Aboriginal children is similar to that documented in some developing countries.
The episodes of invasive H.influenzae disease were serious; 37% of all diagnoses were meningitis. There was an overall invasive H.influenzae disease case-fatality of 3.7%, and over 1.5 Northern Territory hospital beds were occupied every day over the three-year period by a child with the disease.
Most of the hospital bed occupancy occurred in Central Australia and most of the beds were occupied by Aboriginal children. The seriousness of the disease in Central Australia has been aggravated by a recent rapid increase in the prevalence of multiple antibiotic resistance strains.
It is likely that the most important preventive strategy will be immunization. However, because of the high attack rates in infancy, the conjugate H.influenzae vaccine currently licenced for use in the United States is unlikely to prevent many of the cases that occur in Aboriginal children. Nevertheless, newer conjugate vaccines might prove protective in infancy; combined passive/active immunization strategies (ie vaccination of antenatal women followed by immunization of their young infants) are likely to prevent more cases than active immunization strategies alone.
Australian Indigenous HealthInfoNet abstract