From: Journal of Hospital Infection 2000 Jan;44(1): pp 59-64

Interferential therapy machines are used to apply alternating electric currents to patients for the treatment of various musculo-skeletal complaints. The potential for such machines to transfer skin microflora from one patient to another during treatment was investigated. The efficacy of the current disinfection procedure of the machines was also evaluated. In both the laboratory and clinical situation, interferential treatment, (which involves the direct application of electrodes to the skin surface) resulted in the transfer of micro-organisms from the skin of one subject to another. To decrease the likelihood of transmission of micro-organisms via interferential therapy machines, it is recommended that both the suction cups and sponges are disinfected with 70% isopropyl alcohol after the treatment of each patient. The use of disposable electrodes could also be considered.