An outbreak of Salmonella Typhimurium 9 at a school camp linked to contamination of rainwater tanks

In March 2007, an outbreak of gastroenteritis was identified at a school camp in rural Victoria, Australia, affecting about half of a group of 55 students. A comprehensive investigation was initiated to identify the source. Twenty-seven attendees were found to have abdominal pain, diarrhoea and nausea (attack rate 49%). Of 11 faecal specimens tested all were positive for Salmonella Typhimurium definitive phage type 9 (DT9). Of four samples taken from the untreated private water supply, two were positive for DT9. Drinking water from containers filled from rainwater tanks [relative risk (RR) 3.2, P=0.039] and participation in two recreational activities - flying fox (RR 5.3, P=0.011), and beam-balance (RR 3.9, P=0.050) - were indicative of a link with illness. Environmental and epidemiological investigations suggested rainwater collection tanks contaminated with DT9 as being the cause of the outbreak. Increased use of rainwater tanks may heighten the risk of waterborne disease outbreaks unless appropriate preventative measures are undertaken.     

一起纤维支气管镜污染所致感染暴发的分子流行病学调查

目的了解某院一起下呼吸道感染阴沟肠杆菌医院感染暴发的原因,为临床预防和控制医院感染提供依据。方法收集该院呼吸科与胸外科经纤维支气管镜肺泡灌洗诊疗发生下呼吸道阴沟肠杆菌感染患者的流行病学资料,对患者及其周围环境和物品检出菌进行耐药分析,采用脉冲场电泳(PFGE)技术进行基因分型。结果2013年3月8—16日胸外科与呼吸科在内镜中心纤维支气管镜室进行肺泡灌洗患者共15例,后续发生下呼吸道阴沟肠杆菌感染13例,经排查有4例为社区感染(包括首例患者),其余9例均为医院感染;8份环境标本检出2株阴沟肠杆菌,分别来源于纤维支气管镜负压吸引接头、用于修剪一次性可控式吸痰管道的剪刀。将患者与环境检测得到的阴沟肠杆菌15株进行药敏结果筛选,选出药敏结果相似的有11株菌,其中环境2株、住院患者6株、社区患者3株。11株阴沟肠杆菌PFGE分型显示,有8株菌基因型相同,其中6株来自于胸外科患者,2株来自于负压吸引接头与用于一次性可控式吸痰管道的剪刀;另3株基因型相同,来自于呼吸科与胸外科。结论此次感染暴发是由纤维支气管镜污染同一株阴沟肠杆菌引起,该菌对临床常用抗菌药物较敏感,此类事件应引起临床的高度重视,采用必要措施切断传播流行是控制关键。     

Outbreak of healthcare-associated infection and colonization with multidrug-resistant Salmonella enterica serovar Senftenberg in Florida.

BACKGROUND: In July 1999, a rare strain of multidrug-resistant Salmonella enterica serovar Senftenberg was isolated from the sputum of a trauma patient. Over a 6-year period (1999-2005) in northeast Florida, this Salmonella serovar spread to 66 other patients in 16 different healthcare facilities as a result of frequent transfers of patients among institutions. To our knowledge, this is the first outbreak of healthcare-associated infection and colonization with a fluoroquinolone-resistant strain of S. Senftenberg in the United States. OBJECTIVES: To investigate an outbreak of infection and colonization with an unusual strain of S. Senftenberg and assist with infection control measures. DESIGN: A case series, outbreak investigation, and microbiological study of all samples positive for S. Senftenberg on culture. SETTING: Cases of S. Senftenberg infection and colonization occurred in hospitals and long-term care facilities in 2 counties in northeast Florida. RESULTS: The affected patients were mostly elderly persons with multiple medical conditions. They were frequently transferred between healthcare facilities. This Salmonella serovar was capable of long-term colonization of chronically ill patients. All S. Senftenberg isolates tested shared a similar pulsed-field gel electrophoresis (PFGE) pattern. CONCLUSION: A prolonged outbreak of infection and colonization with multidrug-resistant S. Senftenberg was identified in several healthcare facilities throughout the Jacksonville, Florida, area and became established when infection control measures failed. The bacterial agent was capable of long-term colonization in chronically ill patients. Because the dispersal pattern of this strain suggested a breakdown of infection control practices, a multipronged intervention approach was undertaken that included intense education of personnel in the different institutions, interinstitutional cooperation, and transfer paperwork notification.     

An outbreak of neonatal infection with Acinetobacter linked to contaminated suction catheters

An outbreak of multi-drug resistant Acinetobacter spp. infection in the neonatal unit at King Edward VIII hospital in Durban, South Africa, is described. Nine out of a total of 218 neonates were infected during the study period. The outbreak was characterized by early onset infection [median postnatal age 3 days (range 1-23 days)] in pre-term babies [median gestational age 33 weeks (range 30-35 weeks)] with an attributable mortality of 22%. The source of the outbreak, determined by ribotyping, was presumed to be contaminated suction bottles and catheters in the neonatal admission room. Five neonates were successfully treated with ciprofloxacin and amikacin. Enforcement of strict infection control practices curtailed the outbreak.     

An outbreak of Salmonella saint-paul infection associated with beansprouts

In March 1988, there was an outbreak of infection by a strain of Salmonella saint-paul with a distinctive antigenic marker. A total of 143 reports were received between 1 March and 7 June. Preliminary investigations suggested that raw beansprouts were a possible source of infection and a case-control study confirmed the association. S. saint-paul of the epidemic type was isolated from samples of beansprouts on retail sale in different cities in the United Kingdom and from mung bean seeds on the premises of the producer who was most strongly associated with cases. In addition, Salmonella virchow PT34 was isolated from samples of raw beansprouts and was subsequently associated with seven cases of infection. Four other serotypes of salmonella were also isolated from beansprouts. On 8 April the public were advised to boil beansprouts for 15 seconds before consumption, and the premises of the one producer associated with many cases were closed. As a result of these actions there was a significant decrease in the number of infections with S. saint-paul.     

An outbreak of Campylobacter jejuni gastroenteritis linked to meltwater contamination of a municipal well

A large outbreak of Campylobacter jujuni gastroenteritis attributed to contamination of an unchlorinated municipal water system was investigated. Unlike most previous summer outbreaks, this one began in early spring and was attributed to meltwater entering one or more municipal wells. 241 suspected cases were documented, but retrospective information from local health care workers suggested a much larger outbreak. 45 laboratory-confirmed cases participated in a case-control study which showed a significant association between infection and amount of town water consumed. Stool specimens from 29 patients were studied with detailed serotyping by the method of Lior, with eight known serotypes and one previously unknown one identified. It is concluded that intensive surveillance of water quality during periods of spring runoff is essential, and that timely reporting of disease outbreak patterns in emergency department settings is necessary to protect the public's health.     

An outbreak of multidrug-resistant Pseudomonas aeruginosa infection associated with contamination of bronchoscopes and an endoscope washer-disinfector

Over a two-month period, two distinct types of Pseudomonas aeruginosa resistant to ceftazidime and azlocillin were isolated from bronchial specimens of ITU patients who had been previously bronchoscoped. The source of the outbreak was probably a faulty contaminated bronchoscope washer-disinfector which had been purchased a year earlier but not properly maintained. This paper describes the outbreak, the identification and elimination of the source, and the steps taken to prevent recurrence. Several automated, closed washer-disinfectors had been bought by the hospital in response to health and safety concerns about glutaraldehyde disinfection toxicity, but the operation and maintenance of these machines had not been supervised. Several other washer-disinfectors were also found to be faulty. The potential hazards of automated endoscope washer-disinfectors and the importance of controlled professional maintenance, servicing and training is discussed.     

Multistate outbreak of human Salmonella infections associated with exposure to turtles--United States, 2007-2008

Turtles and other reptiles have long been recognized as a source of human Salmonella infections. To prevent turtle-associated Salmonella infections in humans, the sale and distribution of small turtles (i.e., those with a carapace length of less than 4 inches) has been prohibited in the United States since 1975. Despite this prohibition, small turtles remain available to the public from various sources, including pet shops, flea markets, street vendors, and Internet websites. In October 2007, the North Carolina Division of Public Health (NCDPH) notified CDC of human infections caused by Salmonella serotype Paratyphi B L (+) tartrate (+) (Salmonella Paratyphi B var. Java) in several states. Salmonella Paratyphi B var. Java is a nontyphoidal strain of Salmonella that causes gastroenteritis. This report describes the results of the epidemiologic and laboratory investigation conducted by CDC and state and local health departments during October 2007-January 2008. The findings document an ongoing, multistate outbreak of Salmonella Paratyphi B var. Java infections, with the first reported illness onset occurring on May 4, 2007. Many of these infections have occurred in young children and have been associated with exposure to small turtles. Prohibiting the sale and distribution of small turtles likely remains the most effective public health action to prevent turtle-associated salmonellosis.     

一类罕见硫化氢阴性山夫登堡沙门菌腹泻株的分子溯源

[目的]研究一类罕见硫化氢阴性山夫登堡沙门菌腹泻菌株遗传克隆特征。[方法]收集、分析本地区参加全球沙门菌监测(GSS)腹泻病例中分离的山夫登堡沙门菌生化、编码SPI-1毒力岛基因(hilA、invA)和耐药特征;应用Riboprinter(r)(RP)DNA指纹图谱系统比较表型典型与不典型菌株的核糖体分型;通过Pluse Net China数据库中同型菌株的脉冲凝胶电泳(PFGE)图谱聚类比较分子型谱。[结果]2006年长宁区GSS监测病例分离出19株山夫登堡沙门菌,其中10株属于硫化氢阴性和SPI-1毒力岛缺失的表型变异菌株。RP分型证实发生变异的山夫登堡沙门菌与典型菌株间分属2个不同的克隆。Pluse Net China数据库将包括长宁区19株山夫登堡沙门菌在内的36株山夫登堡腹泻株共分18种PFGE带型。长宁区的表型变异株优势型分属4型(2株)和6型(6株),典型菌株的优势型分属11型(1株)、17型(4株)和23型(2株)。聚类分析显示,表型变异株的克隆在遗传相似度上高于典型株。[结论]分子溯源证实,SPI-1毒力岛缺失的山夫登堡沙门菌变异菌株与典型菌株同样具有引发局部爆发的致病性。2006年长宁区分离的硫化氢阴性山夫登堡沙门菌变种腹泻株与2002年深圳市的1例食物中毒案例分离的2株SPI-1毒力岛缺失株存在同源性。     

An outbreak of infections with a new Salmonella phage type linked to a symptomatic food handler.

In December 2001, the South Australian Communicable Disease Control Branch investigated an outbreak of gastrointestinal illness linked to a Korean style restaurant in metropolitan Adelaide. Twenty-eight people were identified as having experienced gastrointestinal symptoms subsequent to dining at the restaurant between 9 and 12 December 2001. A case-control study implicated mango pudding dessert (OR 16.67 95% CI 2.03-177.04) and plain chicken (OR 10.67 95% CI 1.04-264.32). Nineteen cases and one food handler submitted faecal specimens that grew Salmonella Typhimurium 64var. Two samples of mango pudding and one sample of pickled Chinese cabbage also grew Salmonella Typhimurium 64var. The infected food handler reported an onset of illness 2 days before cases first reported eating at the restaurant. The food handler's only role was to prepare the mango pudding dessert in an area external to the restaurant's kitchen. Illness was strongly associated with consumption of a contaminated mango pudding dessert, with contamination most likely resulting from the symptomatic and culture positive food handler who prepared the dish. This outbreak demonstrates the importance of excluding symptomatic food handlers, and the need for appropriately informing and educating food handlers regarding safe food handling procedures. Restaurants with staff and management from non-English speaking backgrounds should be specifically targeted for education that is both culturally sensitive and language specific.     

A Salmonella Typhimurium 197 outbreak linked to the consumption of lambs' liver in Sydney, NSW

We identified an increase in the number of cases of Salmonella Typhimurium phage type 197 in New South Wales in February 2005. Cases were predominantly of Lebanese descent. To identify risk factors for illness, we conducted an unmatched case-control study including 12 cases and 21 controls. Eight of 12 cases (67%) and no controls reported eating lambs' liver (OR incalculable, P<0.05), and seven of nine cases (78%) and one of 21 controls (5%) reported eating fresh fish (OR 70.0, P<0.05). Among participants who did not eat liver, there was a strong association between eating fish and illness (OR 60.0, P<0.05). The fish was from divergent sources. Five cases had bought the liver from two different butcher's shops, which obtained the lambs' liver from a single abattoir. Consumption of liver is a risk for salmonellosis. Traditional dishes may place some ethnic groups at increased risk of foodborne disease.