重症监护病房鲍曼不动杆菌和铜绿假单胞菌的分布及耐药性监测

目的探讨医院重症监护病房(ICU)鲍曼不动杆菌及铜绿假单胞菌临床分离株的分布及耐药性特点。方法回顾性调查2006年7月至2010年6月ICU患者中分离出的鲍曼不动杆菌和铜绿假单胞菌的临床感染情况,对111株鲍曼不动杆菌和73株铜绿假单胞菌的药敏结果进行统计分析,所有数据采用WHONET 5.5软件进行分析。结果鲍曼不动杆菌及铜绿假单胞菌在呼吸道标本中检出率最高(76.1%),其次是CVP导管尖端(8.7%),鲍曼不动杆菌对临床常用抗菌药物耐药率85%的有8种,对亚胺培南的耐药率也达70.3%,耐药率最低的仅有头孢哌酮/舒巴坦(17.1%);铜绿假单胞菌对替卡西林、亚胺培南有较高的耐药率,分别为45.2%、41.1%,对其他抗菌药物耐药率均25%。结论下呼吸道是ICU患者鲍曼不动杆菌和铜绿假单胞菌感染的主要部位;ICU患者感染以鲍曼不动杆菌和铜绿假单胞菌为主,鲍曼不动杆菌较铜绿假单胞菌耐药及多重耐药性严重。     

ICU革兰阴性菌院内感染病原菌及耐药变化

目的探讨ICU革兰阴性菌院内感染的病原菌及抗生素耐药情况,为临床防治提供依据。方法对温州医学院附属第一医院ICU2002年1月-2004年12月院内感染的所有标本分离的革兰阴性菌及耐药性进行回顾性分析。结果革兰阴性菌院内感染的部位主要在下呼吸道,其次为尿路。372株G^-菌中,前5位的分别是鲍曼不动杆菌62株（16．67％）、洋葱假单胞菌61株（16．4％）、铜绿假单胞菌58株（15．59％）、嗜麦芽窄食假单胞菌41株（11．02％）,肺炎克雷伯杆菌34株（9．14％）。3年中,鲍曼不动杆菌和嗜麦芽窄食假单胞菌所致的院内感染有所增加;在细菌耐药性方面,G^-菌的耐药率普遍提高,对头孢哌酮／舒巴坦（13．25％）、哌拉西彬他唑巴坦（23．93％）、头孢他啶（39．66％）、美罗培南（32．17％）、奈替米星（48．36％）的耐药率〈50％,但对亚胺培南高达50．87％。结论ICU院内感染革兰阴性菌对除头孢他啶外的3代头孢耐药率普遍高,对亚胺培南耐药率高,加强细菌耐药性检测,合理使用抗生素很关键。     

烧伤病房难愈性创面病原菌分布及耐药性分析

目的 分析烧伤病房难愈性创面病原菌分布及耐药性,为临床合理选用抗生素提供依据.方法 对2006年1月至2012年6月间中国人民解放军第八五医院烧伤病房收治的难愈性创面患者创面分离出的病原菌,采用K-B纸片扩散法进行药物敏感试验,分析病原菌耐药性.结果 分离出病原菌154株,革兰阳性菌62株,占40.26％;革兰阴性菌92株,占59.74％.常见病原菌为金黄色葡萄球菌、铜绿假单胞菌和鲍曼不动杆菌.烧伤难愈性创面中金黄色葡萄球菌最多见,压迫性溃疡创面中常见铜绿假单胞菌和鲍曼不动杆菌,其他难愈性创面中铜绿假单胞菌最常见.创面革兰阳性菌对利奈唑烷和呋喃妥因的耐药率较低,革兰阴性菌对头孢哌酮/舒巴坦、阿米卡星、亚胺培南、氨曲南和头孢西丁的耐药率较低,无万古霉素耐药菌.常见病原菌中金黄色葡萄球菌和鲍曼不动杆菌的耐药率较高,铜绿假单胞菌的耐药率较低.结论 不同病因的难愈性创面病原菌分布不同,引起难愈性创面的病原菌主要为多重耐药金黄色葡萄球菌和鲍曼不动杆菌.     

革兰阴性杆菌10年耐药性变化分析

目的 对重庆医科大学附属第二医院2001年1月1日至2009年12月31日10年临床标本中分离的主要革兰阴性杆菌耐药性变化进行分析,为临床合理用药提供依据.方法 采用回顾性方法对十年间大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌和不动杆菌的药敏结果用WHONET 5.4软件进行统计分析.结果 大肠埃希菌、肺炎克雷伯菌对亚胺培南耐药率小于5％;对阿米卡星、哌拉西林/他唑巴坦、头孢吡肟耐药率小于30％;对三代头孢、头孢西丁和氨曲南耐药率为40％左右;对青霉素类、喹诺酮类和磺胺类耐药率大于50％.铜绿假单胞菌对头孢他啶、头孢吡肟和亚胺培南耐药率小于40％;对其余监测抗生素耐药率大于50％.不动杆菌属对亚胺培南耐药率小于25％(2009年除外),对其余监测抗生素耐药率很高,维持在50％ ～ 96％.铜绿假单胞菌、鲍曼不动杆菌泛耐药菌检出率分别为0～14％和0～48％.结论 革兰阴性杆菌对常用抗菌药物的耐药已非常普遍,且有逐年升高的趋势;肠杆菌科对碳青霉烯类、阿米卡星、哌拉西林/他唑巴坦、头孢吡肟耐药率相对较低;非发酵菌耐药性增加明显,铜绿假单胞菌、不动杆菌泛耐菌增加明显;严格控制抗菌药物的应用及耐药菌和泛耐药菌的传播和爆发流行已迫在眉睫.     

2007年至2009年3种非发酵革兰阴性杆菌耐药性分析

目的研究自临床分离的铜绿假单胞菌、鲍曼不动杆菌、嗜麦芽寡养单胞菌等3种非发酵革兰阴性杆菌的耐药性及其变迁,为合理使用抗菌药物提供依据。方法临床标本按常规方法分离培养,用生物梅里埃API分析系统鉴定细菌种类,根据CLSI规定的标准,采用纸片扩散法进行体外药敏测定,WHONET软件进行统计分析。结果 2007年至2009年共分离到铜绿假单胞菌310株、鲍曼不动杆菌280株和嗜麦芽寡养单胞菌86株。其中亚胺培南不敏感的铜绿假单胞菌为32.5%,亚胺培南不敏感的铜绿假单胞菌对其他药物的耐药率也明显高于亚胺培南敏感菌株;鲍曼不动杆菌对大部分抗生素的耐药率都高于60%,对亚胺培南、美罗培南3年总的敏感率为51.6%和48.2%;嗜麦芽寡养单胞菌对米诺环素的敏感率为93.8%。比较3年耐药率的变迁,2009年部分抗菌药物耐药性增长的势头得到遏制。结论非发酵菌是引起院内感染的重要病原菌,对多种抗菌药物都有较高的耐药性,合理使用抗生素,加强医院感染的控制对减少细菌耐药性的产生有非常重要的作用。     

辽宁省近5年痰培养主要病原菌分布及临床意义

了解住院患者痰培养的病原菌分布及其对常用抗菌药物的耐药情况,为临床合理用药提供参考。回顾性分析辽宁省2015年1月至2019年12月共3 878份痰标本感染菌鉴定结果和铜绿假单胞菌(Pseudomonas aeruginosa)的药敏试验结果。采用法国梅里埃VITEK 2 Compact全自动微生物鉴定仪进行菌种鉴定,并对从门诊和住院下呼吸道感染患者中分离的785株铜绿假单胞菌进行药物敏感试验分析。结果表明,痰培养病原菌以革兰阴性杆菌为主,占68.9%,其次为真菌。在革兰阴性杆菌中,铜绿假单胞菌占20.2%。铜绿假单胞菌对氨苄西林、呋喃妥英、复方新诺明、头孢呋辛(酯)、头孢曲松、头孢替坦、头孢唑啉的耐药性较高,每年的耐药率均高于95%。而对于阿米卡星、环丙沙星、头孢吡肟、头孢他啶、左氧氟沙星则出现较低的耐药性,5年的耐药率均低于50%。铜绿假单胞菌对阿米卡星、哌拉西林、头孢吡肟、美罗培南、亚胺培南的耐药率有逐年下降的趋势,而对环丙沙星、左氧氟沙星的耐药率有逐年上升的趋势。以上结果表明辽宁省近5年痰培养主要致病菌为革兰阴性杆菌,其中铜绿假单胞菌占很大的比例。铜绿假单胞菌易产生多重耐药性,必须加强耐药性监测,为临床提供最新的耐药性资料,以便更好地控制铜绿假单胞菌的感染,同时也对临床合理使用抗生素有指导意义。     

1052株烧伤创面病原菌及其药敏分析

目的为了指导临床合理应用抗生素,提高治愈。方法所有标本均采用常规细菌培养,纸片扩散法对1052株病原菌行耐药性监测。结果360例患者送检标本1136份,检出1052株病原菌,其中G^-杆菌611株,占总检出率的58．08％,G^-球菌416株（39．54％）,MRSA253株,占金黄色葡萄球菌的60．82％,真菌25株（2．38％）。结论烧伤感染常见为铜绿假单胞菌,不动杆菌,变形杆菌,金黄色葡萄球菌和MRSA,且耐药性强。     

2011～2015年医院呼吸内科常见革兰阴性菌耐药性分析与临床用药探讨

目的：分析2011～2015年我院呼吸内科常见革兰阴性菌的分布情况及耐药性特点,为规范抗生素的合理使用提供依据。方法选用法国梅里埃公司生产的ID 32GD试剂盒,应用ATB Expression全自动分析系统对细菌进行鉴定与药敏试验。结果2011～2015年在我院呼吸内科常见的病原菌分别为肺炎克雷伯菌（31．0％）、大肠埃希菌（21．2％）、铜绿假单胞菌（23．2％）与鲍曼不动杆菌（14．8％）。肺炎克雷伯菌对碳青霉烯类的耐药率几乎为0,对单纯的头孢菌素耐药率相对较高,但对含β‐内酰胺酶抑制剂的头孢菌素类以及阿米卡星有较强的抗菌活性;大肠埃希菌对哌拉西林耐药率高,但对含酶青霉素类有较强的抗菌活性,对碳青霉烯类的耐药率连续5年来均为零;铜绿假单胞菌对磺胺类耐药性较高,对头孢三代、头孢四代及含酶青霉素类与含酶头孢类均有较强的抗菌活性,但敏感性呈逐年下降趋势;鲍曼不动杆菌的耐药率呈逐年上升趋势,仅对含酶的头孢哌酮／舒巴坦敏感（约80％）。结论医院呼吸内科革兰阴性菌仍以肺炎克雷伯菌、大肠埃希菌、铜绿假单胞菌、鲍曼不动杆菌为主。鲍曼不动杆菌耐药性逐年增长的问题已日趋严重,相关部门应定期监测细菌耐药趋势,指导临床合理用药,特别是合理应用抗生素以避免细菌耐药及减少细菌耐药性的发生。     

重症监护室患者血流感染菌谱构成及耐药性分析

目的 了解综合性医院重症监护室患者血流感染病原菌分布及其耐药性.方法 回顾性调查2011年6月至2012年6月南昌大学第二附属医院ICU患者血培养情况,对分离菌株及其药敏结果进行统计分析,所有数据采用WHONET 5.5软件分析.结果 1764例患者血培养共分离获得482株病原菌,总阳性率为27.32％.其中革兰阳性球菌占39.83％(192/482),革兰阴性杆菌占51.04％ (246/482),真菌占8.09％ (39/482).最常见的感染菌分别为凝固酶阴性葡萄球菌、洋葱伯克霍尔德菌、大肠埃希菌、鲍曼不动杆菌、肺炎克雷伯菌、铜绿假单胞菌及金黄色葡萄球菌.金黄色葡萄球菌和表皮葡萄球菌的耐甲氧西林发生率分别为88.24％及90.48％,对青霉素的耐药率均为100％,未检测到耐万古霉素的葡萄球菌.金黄色葡萄球菌与表皮葡萄球菌比较,耐药率有统计学意义的只有复方新诺明,耐药率分别为5.88％和63.49％,金黄色葡萄球菌对复方新诺明(5.88％)和夫西地酸(11.76％)耐药率较低;大肠埃希菌与肺炎克雷伯菌耐药率最低的是亚胺培南,分别为13.04％及11.11％;铜绿假单胞菌对亚胺培南的耐药率为20.00％,而鲍曼不动杆菌对亚胺培南的耐药率高达92.68％.结论 凝固酶阴性葡萄球菌、洋葱伯克霍尔德菌、鲍曼不动杆菌等是重症监护室患者血流感染的常见病原菌,其耐药及多重耐药性均较严重.     

主要医院感染病原菌的变迁及其耐药性分析

目的 分析永康市第一人民医院主要医院感染病原体和耐药性变迁,指导临床合理使用抗菌药物,防治医院感染。方法 用全国医院感染监测网软件,统计2000年1月～2003年12月医院感染主要病原体及其药敏结果,χ^2检验分析。结果 该院主要医院感染病原体依次是鲍曼不动杆菌、大肠埃希菌、金黄色葡萄球菌、肺炎克雷伯菌、铜绿假单胞菌、类白喉棒状杆菌、表皮葡萄球菌和阴沟肠杆菌。耐药率呈逐年增高趋势,但不同的细菌耐药率各具特点。革兰阳性（G^＋）菌对万古霉素的耐药率均为0,对利福平的耐药率均较低（0％～13．6％）,类白喉棒状杆菌对米诺四环素、妥布霉索和头孢哌酮的耐药率也较低。革兰阴性（G^-）菌对亚胺培南的耐药率均低（0％～36．8％）,鲍曼不动杆菌和阴沟肠杆菌具有多重高耐药性,铜绿假单胞菌对头孢吡肟、氨基糖苷类和环丙沙星的耐药率尚在较低水平（0％～36．4％）,大肠埃希菌和肺炎克雷伯菌的耐药性相似,对哌拉西林-他唑巴坦、头孢西丁的耐药率较低（0％～38．6％）。结论 细菌的耐药性与抗菌药物的使用及细菌自身复杂的耐药特性有关,及时送检感染部位标本,根据细菌药敏,合理使用抗菌药物控制感染,对降低细菌耐药率有现实意义。     

临床病原菌种类及耐药性监测

目的 探讨病原菌种类及其对抗菌药物的耐的耐药状况。方法 收集１９９８年１月－１９９９年１２月临床感染标本分离的病原菌并分析其种类,药敏试验采用Ｋｉｒｂｙ－Ｂａｕｅｒ纸片扩散法。结果 １１８２株病原菌,革兰氏阳性球菌６０４株（５１．１％）,革兰氏阴性杆菌５７８株（４８．９％）。病原菌以金黄一萄球菌、大肠埃希菌、表皮葡萄球菌、铜绿假单胞菌最多见。去甲万古霉素、阿米卡星、新霉素对革兰氏阳性球菌抗菌作用较     

132株奇异变形杆菌的临床分布及药敏分析

目的了解宁波市妇女儿童医院奇异变形杆菌的临床分布和耐药情况,为临床合理用药提供依据。方法对该院2009年6月1日至2011年5月31日期间分离的132株奇异变形杆菌进行分析,菌株鉴定采用法国生物梅里埃公司的VITEK 60分析仪,药敏试验采用K-B法,用参考菌株作质量控制。结果该院分离的奇异变形杆菌主要来自尿液（51.50%）,其次是创口分泌物（21.21%）,再次是阴道分泌物（19.70%）,其他（7.59%）。对奇异变形杆菌敏感率较高的抗生素是：丁胺卡那霉素、氨曲南、美罗培南、亚胺培南、头孢唑林、头孢呋辛酯、头孢曲松、头孢他啶、头孢噻肟、马斯平、头孢西丁、罗红霉素、氨苄西林/舒巴坦、哌拉西林/他唑巴坦和头孢哌酮/舒巴坦。结论加强奇异变形杆菌的分离鉴定及耐药性的测定,是临床合理应用抗生素的重要依据。     

平湖市第一人民医院儿科患者主要病原菌分布及耐药性分析

目的了解和探讨平湖市第一人民医院儿科感染的常见病原菌的分布状况及耐药情况。方法对该院2012年1月至2012年12月儿科患者送检的合格标本进行细菌培养和药敏试验,并统计分析。结果分离出305株病原菌,其中革兰阳性球菌166株,占54. 5%,革兰阴性杆菌134株,占43. 9%,真菌5株,占1. 6%。革兰阳性球菌中前几位依次为金黄色葡萄球菌82株,占49.4%,人葡萄球菌27株,占16. 3%,表皮葡萄球菌27株,占16. 3%,溶血葡萄球菌17株,占10. 2%。革兰阴性杆菌中前几位依次为肺炎克雷伯菌42株,占30. 2%,大肠埃希菌28株,占20. 1%,鲍曼不动杆菌21株,占15. 1%,阴沟肠杆菌15株,占10. 8%,不同病原菌对常用抗菌药物呈现不同程度的耐药,大肠埃希菌的ESBLs阳性率为28. 6%,肺炎克雷伯菌ESBLs阳性率为11.9%。结论该院儿科患者感染的主要病原菌以革兰阳性球菌为主,最常见为金黄色葡萄球菌,不同病原菌对抗生素的耐药性不同,应加强病原菌的检测及耐药性监测,严格执行消毒灭菌操作的各项规定,尽早进行细菌鉴定和药敏试验,临床应根据药敏结果选择用药,合理使用抗菌药物。     

Infectivity and resistance to antibiotics of bacterial strains isolated from patients hospitalised in intensive care units

The aim of this study was to evaluate the frequency of isolation and antimicrobial resistance testing of bacterial strains isolated from clinical specimens from patients hospitalized in three Intensive Care Units in Wroc?aw. The susceptibility of bacteria (107 strains) to selected antibiotics was determined. The results clearly show that non-fermentative rods were identified as the main agents causing pneumonia (58% of isolates). The second commonest pathogens were Gram-positive cocci (29%). The P. aeruginosa and E. cloacae strains were resistant to ampicillin, amoxicillin/clavulanate, cefuroxime and cefotaxime. All isolates of A. baumanii were susceptible only to imipenem. The rods of K. pneumoniae and E. coli were resistant to ampicillin, about 55% strains of both bacteria were sensitive to other antibiotics, except piperacillin/tazobactam, imipenem and ciprofloxacin. About 90% of methicillin resistant S. epidermidis strains were resistant to all antibiotics, except vancomycin (100% isolates were sensitive). ESBL were detected among E. cloace, K. pneumoniae and E. coli. We found P. aeruginosa rods producing MBL.     

In Vitro Studies of Semisynthetic α- (Substituted-Ureido) Penicillins

The activity of three alpha-(substituted-ureido) penicillins was evaluated in vitro against 599 clinical isolates of gram-negative bacilli, by use of the broth-dilution technique. At a concentration of 12.5 mug or less/ml, BL-P1597 inhibited 90% of isolates of Pseudomonas sp., 56% of Enterobacter sp., 67% of indole-positive Proteus spp., 72% of Escherichia coli, and 85% of Proteus mirabilis. BL-P1654 had similar activity, whereas BL-P1532 was much less active. At a concentration of 25 mug or less/ml, BL-P1597 also inhibited nearly 60% of isolates of Klebsiella sp. and nearly 40% of Serratia sp. BL-P1597 and BL-P1654 were as active as ampicillin and carbenicillin against E. coli and P. mirabilis. They were less active than carbenicillin against indole-positive Proteus spp. Both drugs were substantially more active than carbenicillin against Pseudomonas sp. A strain of Pseudomonas sp. which developed resistance to carbenicillin also developed resistance to the alpha-(substituted-ureido) penicillins simultaneously.     

Antimicrobial profile of ceftazidime: the situation in three larger hospitals in Prague between 1981 and 1983

As a part of preclinical trials of 2,996 clinical isolates from three larger hospitals in Prague were qualitatively and quantitatively assayed for in vitro sensitivity to ceftazidime. In gramnegative bacteria the incidence of resistance to ceftazidime in strain of Enterobacter, Serratia Proteus and Pseudomonas species ranged from 4% to 6% of strains. In grampositive bacteria only strains of enterococci, listeriae and anaerobic bacteria are excluded from the action of this broad-spectrum antibiotic. According to present experiences the antipseudomonal activity of ceftazidime is approximately the same as that of cefsulodine and cefoperazone. Alarmingly, one of the Pseudomonas aeruginosa isolates was found to show a distinct multiresistance to all available lactam, aminoglycoside and broad-spectrum antimicrobials, including ceftazidime.     

Comparison of antimicrobial resistance patterns between clinical and sewage isolates in a regional hospital in Taiwan

Aims:  To compare bacterial populations and antimicrobial resistance patterns between clinical and sewage isolates from a regional hospital in northern Taiwan. The dissemination of antibiotic-resistant bacteria from hospital compartments to the hospital sewage treatment plant was examined.
Methods and Results:  A total of 1020 clinical isolates and 435 sewage isolates were collected between July and September 2005. The percentages of Gram-negative bacteria from the clinical and sewage isolates were 87·2% and 91·0%, respectively ( P  =   0·033). Escherichia coli were the leading bacterial isolates in both groups. Antimicrobial susceptibility testing showed a significant difference ( P  <   0·001) in resistance to ampicillin (85·6% vs 94·1%), ampicillin/sulbactam (31·7% vs 55·4%), cefazolin (29·2% vs 71·5%) and cefuroxime (20·7% vs 61·9%) between clinical and sewage coliform isolates, respectively.
Conclusions:  The sewage isolates had higher antimicrobial resistance rates than the clinical isolates from the same hospital.
Significance and Impact of the Study:  The low efficacy of the hospital sewage treatment may contribute to the dissemination of multidrug resistant bacteria from this hospital compartments to the environment. Practices which limit the disposal of antimicrobial agents into the wastewater system may be the possible measure to prevent the selection of multidrug-resistant bacteria from sewage treatment plants.     

Aerobic bacteria from nasal discharge of goats suffering from clinical PPR: isolation and identification

Bacteriological isolation of aerobic bacteria from nasal discharge of achondroplastic West African dwarf goats showing clinical signs of peste des petits ruminants (PPR), and the laboratory procedures carried out for the identification of the isolates are described. From a total of forty nasal swabs obtained seventy five isolates were recovered. The percentage frequency of isolation of different organisms in descending order of occurrence is as follows: Staphylococcus 44.0%; Streptococcus 22.67%; Neisseria 12.00%; Pasteurella 10.67%; Pseudomonas 4.00%; Proteus 4.00% and Corynebacterium 1.33%. A further break-down using biochemical tests revealed that Staphylococcus aureus accounted for 30.67% of the total bacteria isolates; Staphylococcus epidermidis 13.33%; Streptococcus viridans 18.67%; Streptococcus pyogenes 4.00%; Neisseria catarrhalis 12.00%; Proteus mirabilis 2.67%; Proteus rettgeri 1.33%; Pseudomonas aeruginosa 5.33%; Pasteurella multocida 4.00%; Pasteurella haemolytica 6.67% and Corynebacterium pyogenes 1.33%.     

2014—2016年某院铜绿假单胞菌耐药性监测

摘要：目的 分析铜绿假单胞菌的分布和耐药性变化,为临床防治铜绿假单胞菌感染提供依据。方法 收集成都大学附属医院2014—2016年所分离的铜绿假单胞菌,采用VITEK 2-Compact全自动细菌鉴定系统进行鉴定和药敏试验,采用WHONET 5.6软件对数据进行分析。结果 3年间共分离出1 945株铜绿假单胞菌,多重耐药铜绿假单胞菌分离率为34.2%（666/1945）。标本来源以呼吸道为主,占82.2%（1598/1945）。科室分布以呼吸内科最多,ICU其次。铜绿假单胞菌对头孢曲松和头孢噻肟的耐药率最高,均＞57.0%;对阿米卡星耐药率最低,为2.0%。3年来铜绿假单胞菌对17种抗生素的耐药率呈整体上升的趋势。结论 铜绿假单胞菌对头孢曲松、头孢噻肟、亚胺培南耐药率较高,对阿米卡星耐药率较低。铜绿假单胞菌的耐药率呈整体上升的趋势,应重视细菌耐药性的监测,以延缓耐药性产生、促进临床合理用药。     

Bacteriophage Typing of Proteus mirabilis, Proteus vulgaris, and Proteus morganii

A bacteriphage typing scheme for differentiating Proteus isolated from clinical specimens was developed. Twenty-one distinct patterns of lysis were seen when 15 bacteriophages isolated on 8 Proteus mirabilis, 1 P. vulgaris, and 1 P. morganii were used to type 162 of 189 (85.7%) P. mirabilis and P. vulgaris isolates. Seven phages isolated on 3 P. morganii were used to type 13 of 19 (68.4%) P. morganii isolates. Overall, 84.1% of the 208 isolates were lysed by at least 1 phage at routine test dilution (RTD) or 1,000 x RTD. Fifty isolates, retyped several weeks after the initial testing, showed no changes in lytic patterns. The phages retained their titers after storage at 4 C for several months. A computer analysis of the data showed that there was no relationship between the source of the isolate and bacteriophage type. This bacteriophage typing system may provide epidemiological information on strains involved in human infections.