Filling the gaps in the Healthy Skin program

The Filling the Gaps (FTG) project was a collaboration between three CRC for Aboriginal Health partners utilising laboratory, clinical and epidemiological methods and building on work undertaken by the East Arnhem Healthy Skin project and previous work. The four themes of the FTG project are:

• Theme 1: Scabies resistance and the immunology of infection.
• Theme 2: Determinants of persistent/recurrent scabies.
• Theme 3: Treatment of skin sores and the role of antibiotic resistance.
• Theme 4: Epidemiology of group A streptococcus (GAS) isolates in East Arnhem and Queensland Indigenous communities.

The emergence of antibiotic resistance among skin bacteria and drug resistance among scabies mites are two issues likely to be major obstacles to the sustainability of community-based programs. Also of serious concern is the emergence in Australia of community-acquired methicillin resistant Staphylococcus aureus (CAMRSA), which has increasingly been found to involve remote Indigenous communities. The FTG proposal supplemented activities aimed at ensuring effectiveness of a potential GAS vaccine that may eventually prevent skin disease from progressing to the more serious illnesses of rheumatic fever, rheumatic heart disease and streptococcal kidney disease.

The primary objectives of the FTG project are:

• Better understanding of the types of bacteria that cause skin infections in Aboriginal communities in the Northern Territory and Queensland and whether these will be preventable by a vaccine currently under development at Queensland Institute of Medical Research.
• Better understanding of how bacteria and scabies mites develop resistance to treatments and identification of alternative therapies.
• Consolidation of evidence about the causes and associated risk factors for persistent and recurrent scabies infestations.
• Identification of the mechanism of the allergic reaction responsible for many of the manifestations of scabies infestation.

Over three years the FTG researchers utilised laboratory, clinical and epidemiological methods to evaluate drug resistance levels and to evaluate alternative drugs for scabies, GAS and CAMRSA. All scabies and bacterial samples used come from the seven communities already being studied as part of other Healthy Skin program projects. 

The original project milestones are as follows:

• Nov 2005: Commence analysis of scabies mites, skin sore and throat swabs collected from the East Arnhem Project. Commence cross-sectional skin swabbing surveys in Queensland.
• Feb 2006: Subject to results of community consultation, submit funding application for a Randomised Control Trial or observational study of various treatment protocols.
• Dec 2006: Construction of S. scabiei genomic and 5’ cDNA libraries at Menzies School of Health Research. Generation of mdx -/- mice as mouse model for scabies at Queensland Institute of Medical Research. Complete follow-up of subjects recruited for case-control study.Summary report on progress of GAS collection and typing.Summary report of types of bacteria and their antibiotic resistance profiles from the first year of swabbing studies in East Arnhem and Queensland.
• March 2007: Complete follow-up of subjects recruited for case-control study.
• July 2007: Complete final report for case-control study.
• Dec 2007: Characterise the genes associated with scabies resistance. Begin development of a diagnostic test for resistance in scabies mite populations. Evaluation of drug resistance levels and evaluation of alternative drugs for both scabies and GAS and CAMRSA. Report of epidemiology of GAS and staph isolates, and their antibiotic resistance profiles from the swabbing studies in East Arnhem and Queensland.

Related resources:

• Tong, S. Y. C, McDonald, M. I., Holt, D. C. & Currie, B. J. 2008, ‘Global Implications of the Emergence of Community-Associated Methicillin-Resistant Straphylococcus aureus in Indigenous Populations’, Clinical Infectious Diseases, vol. 46, pp. 1871–8.
• Clucas, D. B., Carville, K. S., Connors, C., Currie, B. J., Carapetis, J. R. & Andrews, R. M. 2008, ‘Disease Burden and Health-Care Clinic Attendances for Young Children in Remote Aboriginal Communities of Northern Australia’, Bulletin of the World Health Organization, vol. 86(4), pp. 275–80.
• Kearns, T. 2008, ‘Treating Skin Infections in NT Indigenous Communities’, Every Child Magazine, vol. 14(2), p. 14.
• Mounsey, K. E., Holt, D., McCarthy, J., Currie, B., Walton, S. 2008, ‘Scabies: Molecular perspectives and therapeutic implications in the face of emerging drug resistance’ Future Microbiol, vol. 3(1), pp. 57–66.
• Pasay, C., Arlian, L., Morgan, M., Uyszenski-Mohor, D., Rose, A., Holt, D., Walton, S. & McCarthy, J. 2008, ‘High-resolution Melt Analysis for the Detection of a Mutation Associated with Permethrin Resistance in Population of Scabies Mites’, Medical and Veterinary Entomology, vol. 22, pp. 82–8.
• Mounsey, K. E., Dent, J. A., Holt, D. C., McCarthy, J., Currie, B. J. & Walton, S. F. 2007, ‘Molecular Characterisation of a pH-gated Chloride Channel from Sarcoptes scabiei’, Invertebrate Neuroscience, in press, 31/5/07.
• Fischer, K., Holt, D. C., Currie, B. J., Walton, S. F. & Kemp, D. J. 2006, ‘Scabies Mite Inactivated Protease Paralogues. ICS 1289’, Streptococci and Streptococcal Disease, vol. 1289, pp. 85–8.
• Mounsey, K. E., Holt, D. C., McCarthy, J. & Walton, S. F. 2006, ‘Identification of ABC Transporters in Sarcoptes scabiei’, Parasitology vol. 132(2), pp. 1–10.
• Pasay, C., Walton, S., Fischer, K., Holt, D. & McCarthy, J. 2006, ‘PCR-based Assay to Survey for Knockdown Resistance to Pyrethroid Acaricides in Human Scabies Mites (Sarcoptes scabiei var hominis)’, Am J Trop Med Hyg, vol. 74, pp. 649–57. (IF 2.0)
• Willis, C., Fischer, K., Walton, S., Currie, B. J. & Kemp, D. J. 2006, ‘Scabies Mite Inactivated Serine Protease Paralogues Are Present both Internally in the Mite Gut and Externally in Faeces’, Am J Trop Med Hyg, vol. 75(4), pp. 683–7.