Sullivan P K, Conner-Kerr T A, Smith S T
Department of Clinical Laboratory Science, School of Allied Health Sciences, East Carolina University, Greenville, NC 27858-4353, USA.
Ostomy Wound Manage. 1999 Oct;45(10):50-4, 56-8.
Streptococcus pyogenes (group A streptococcus--GAS) is a common cause of necrotizing fasciitis (NF)--a severe infection of the subcutaneous soft tissue. The purpose of this study was to determine if the topical therapy ultraviolet light C (UVC) is effective in killing GAS in vitro and to evaluate the most effective treatment parameters for use with UVC therapy. Five replications of GAS at 10(8) organisms/mL were plated. The cultures were treated with a UVC light 1 inch from the surface. Irradiation times were as follows: 0, 2, 3, 4, 5, 15, 30, 45, 60, 90, 120, and 180 seconds. Bacterial cultures were incubated and colony counts performed. A second set of GAS cultures were exposed to UVC for 30, 90, and 120 seconds either once daily (qd) or twice daily (bid). Kill rates were 99.9% for GAS at 4 seconds to 180 seconds. Kill rates of 99.9% were also obtained at 30 seconds and 90 seconds when UVC treatment was given either qd or bid. This data indicates that UVC is bactericidal for GAS at times as short as 4 seconds. In addition, UVC treatment was not effective when administered through thin film dressings.
化脓性链球菌（A组链球菌——GAS）是坏死性筋膜炎（NF）的常见病因，坏死性筋膜炎是一种皮下软组织的严重感染。本研究的目的是确定局部治疗用的紫外线C（UVC）在体外杀死GAS是否有效，并评估UVC治疗的最有效参数。接种了浓度为10(8)个菌/mL的GAS，共进行五次重复培养。培养物在距离表面1英寸处用UVC灯进行处理。照射时间如下：0、2、3、4、5、15、30、45、60、90、120和180秒。对细菌培养物进行孵育并进行菌落计数。第二组GAS培养物每天照射UVC 30、90和120秒一次（qd）或两次（bid）。在4秒至180秒时，GAS的杀灭率为99.9%。当每天照射一次（qd）或两次（bid）时，在30秒和90秒时也获得了99.9%的杀灭率。该数据表明，UVC在短至4秒的时间内对GAS具有杀菌作用。此外，通过薄膜敷料进行UVC治疗无效。
