Phase change material for thermotherapy of Buruli ulcer: modelling as an aid to implementation

A mathematical model was developed and validated to predict the thermal behaviour of a heat application device based on a phase change material (pcm) for the heat treatment of Mycobacterium ulcerans infection (Buruli ulcer). The thermal model allows the prediction of skin surface temperatures and an optimization of the amount of pcm with respect to discharge time. A first prototype of such a pcm bandage was manufactured and used in a proof-of-principal trial in Cameroon. The experimental data were analysed and yielded no difference in thermoregulatory response between people living in hot or moderate climate. Short-term maximum skin surface temperatures of 42 degrees C are tolerable; the pcm bandage keeps the skin surface temperature above 40 degrees C for about four to five hours. This makes such pcm bandages an ideal device for the heat treatment of Buruli ulcer. The pcm bandage is easy to apply, cheap, and thus is well suited for use in low-resource countries.