Disclosed herein is an applicator that can be advanced over an in-situ guidewire and into the subcutaneous tissue or tract prior to CVC placement or replacement, allowing sterilization of the subcutaneous tissue or tract before CVC introduction. The unique shape of the applicator allows sterilization of the skin surface as well as the subcutaneous tissue or tract of the original CVC that lies beneath the skin, which are difficult to reach and effectively sterilize with other applicators.