Treatment of scabies using a tea tree oil-based gel formulation in Australian Aboriginal children: protocol for a randomised controlled trial

Introduction: In remote Aboriginal communities in Australia, scabies affects 7 out of 10 children before their first birthday. This is more than six times the rate seen in the rest of the developed world. Scabies infestation is frequently complicated by bacterial infection, leading to the development of skin sores and other more serious consequences, such as septicaemia and chronic heart and kidney diseases. Tea tree oil (TTO) has been used as an antimicrobial agent for several decades with proven clinical efficacy. Preclinical investigations have demonstrated superior scabicidal properties of TTO compared with widely used scabicidal agents, such as permethrin 5% cream and ivermectin. However, current data are insufficient to warrant a broad recommendation for its use for the management of scabies because previous studies were small or limited to in vitro observations.

Methods and analysis: A pragmatic first trial will examine the clinical efficacy of a simple and low-cost TTO treatment against paediatric scabies and the prevention of associated secondary bacterial infections, with 1:1 randomisation of 200 participants (Aboriginal children, aged 5-16 years and living in remote Australia) into active control (permethrin 5% cream) and treatment (5% TTO gel) groups. The primary outcome for the study is clinical cure (complete resolution). Secondary outcome measures will include relief of symptoms, recurrence rate, adverse effects, adherence to treatment regimen and patient acceptability.

Ethics and dissemination: The project has received approvals from the University of Canberra Human Research Ethics Committee (HREC 16-133), Wurli-Wurlinjang Health Service Indigenous subcommittee and the Aboriginal Medical Services Alliance Northern Territory reference group. The results of this study will be published in core scientific publications, with extensive knowledge exchange activities with non-academic audiences throughout the duration of the project.