containers used for storing and dispensing liquids for medical applications include a closure , and medical connection device include cooperating connector members . an article of manufacture and a method are provided where a plastic outer closure is applied over container closures or over connection devices . the application of the plastic outer closure exerts an antibacterial effect in the juncture area defined by the interface of the outer closure and the container inner closure and neck , or defined by the interface of the outer closure and the connection site of the connector members . the outer closure is of a type of plastic that releases an antibacterial agent , which exerts an antibacterial effect in the juncture area .