Abstract: A medical device for enabling a rescuer to administer mouth-to-mouth resuscitation to a victim while maintaining a sanitary barrier between victim and rescuer, composed of: a sheet of a flexible material forming a barrier to micro-organisms, the sheet being dimensioned to completely cover the victim's mouth and having an opening surrounded by a portion of the sheet which is shaped to allow the rescuer's lips to form an air-tight seal with the victim's lips; members secured to the sheet and located to pass around the victim's ears in order to hold the sheet in place so that the opening is located in front of the victim's mouth; a tubular member defining a confined air passage extending through the opening and having a first portion located to be inserted into the mouth of the rescuer and a second portion located to be inserted into the victim's mouth when the sheet is in place; and a one-way valve fastened to the first portion of the tubular member for permitting free passage of air only from the rescuer to th