An outbreak of Yersinia enterocolitica O:3 infections on an oil tanker

In January 2002, an outbreak of Yersinia enterocolitica O:3 infections occured on 'Asirat', an oil tanker, during its return test voyage from Split, Croatia to Trieste, Italy. Of the 120 crewmembers and workers 22 (18%) suffered from gastrointestinal symptoms. In 17 patients Y. enterocolitica O:3 was isolated from stool samples. All available food and water samples were negative and the source of infection was not determined. Probably a foodborne transmission was involved, although person to person transmission could not be excluded.     

Waterborne gastrointestinal illness at a ski resort. --Isolation of Yersinia enterocolitica from drinking water--.

Approximately 41 percent of the visitors and employees who were at a ski resort in Montana between December 23, 1974, and January 17, 1975, became ill with diarrhea and other gastrointestinal symptoms. The association between illness and water consumption proved to be significant, and the previously noncontaminated water supply was found to contain coliforms. No pathogens except Yersinia enterocolitica were isolated, and it was isolated from two wells serving the area. The role of Y. enterocolitica in this outbreak is not clear, but it was the only organism isolated that is known to be pathogenic.     

Excretion of Yersinia spp. associated with consumption of pasteurized milk

Yersinia enterocolitica biotype 1, serotype O.10K was isolated from 19 patients in the paediatric wards of a district general hospital over a period of 3 months. Fifteen cases were patients on the medical ward. Shortly afterwards, Y. enterocolitica biotype 1, serotype O.6, 30 was isolated from a further 17 patients on this ward in 1 month. The same serotypes of Y. enterocolitica were isolated from the pasteurized milk supplied to the ward. Epidemiological evidence indicated that contaminated pasteurized milk was the source of the yersinia organisms excreted by the patients.     

1997-2010年宁夏回族自治区小肠结肠炎耶尔森菌致病性的基因特征

目的 了解宁夏回族自治区小肠结肠炎耶尔森菌主要毒力基因分布情况和致病性小肠结肠炎耶尔森菌分子分型特征。方法 于1997-2010年在宁夏回族自治区共分离得到283株小肠结肠炎耶尔森菌,用PCR法分析其黏附侵袭位点基因(ail)、耐热肠毒素A基因（ystA）、ystB、黏附素基因（yadA）、毒力活化因子基因（virF）;应用限制性内切酶Not Ⅰ酶切致病性小肠结肠炎耶尔森菌染色体DNA进行脉冲场凝胶电泳(PFGE),利用BioNumerics软件进行聚类分析。结果 209株O∶3、O∶9血清型小肠结肠炎耶尔森菌中ail、ystA、yadA、virF毒力基因阳性,ystB为阴性的占97.6％( 204/209);O∶8血清型和未开展血清分型的菌株5种毒力基因全部阴性;11株O∶5血清型有9株5种毒力基因全部阴性。将致病性菌株进行PFGE分型,根据染色体DNA的Not Ⅰ酶切图谱,将29株O∶3血清型分成12个PFGE带型,包含5株以上的优势PFGE带型有2种。180株O∶9血清型菌株分成13个PFGE带型,包含10株以上的优势PFGE带型有4种,各自是从同一地区猪与家鼠、猪与犬、猪与野兔分离。结论 宁夏地区O∶3、O∶9血清型小肠结肠炎耶尔森菌具有致病性,O∶3逐步成为如今的优势血清型;O∶5、O∶8与血清未分型的菌株无致病性。     

Faecal carriage rate of Yersinia species.

A total of 1,203 unselected routine faecal samples from 1,006 patients were cultured for Yersinia species by a cold enrichment technique. Seventy-five specimens (6.1%) from 63 patients were culture-positive for Yersinia spp. Fifty-two were Yersinia enterocolitica, 22 Yersinia frederiksenii and 1 Yersinia intermedia. The predominant Y. enterocolitica isolates belonged to biotype 1 - serotype 0:6, 30 or serotype 0:5, 27. Y. frederiksenii strains were non-typable. Forty isolates were recovered from 33 patients with gastroenteritis. During the study period 83 Salmonella spp. from 33 patients, 17 Shigella sonnei from 13 patients and 13 Campylobacter jejuni from 12 patients were cultured. Yersinia spp. was isolated in association with salmonella on three occasions, twice with rotavirus and once each with Shigella sonnei, Campylobacter jejuni and Trichuris trichiura.     

Faecal carriage rate of Yersinia species

A total of 1,203 unselected routine faecal samples from 1,006 patients were cultured for Yersinia species by a cold enrichment technique. Seventy-five specimens (6.1%) from 63 patients were culture-positive for Yersinia spp. Fifty-two were Yersinia enterocolitica, 22 Yersinia frederiksenii and 1 Yersinia intermedia. The predominant Y. enterocolitica isolates belonged to biotype 1 - serotype 0:6, 30 or serotype 0:5, 27. Y. frederiksenii strains were non-typable. Forty isolates were recovered from 33 patients with gastroenteritis. During the study period 83 Salmonella spp. from 33 patients, 17 Shigella sonnei from 13 patients and 13 Campylobacter jejuni from 12 patients were cultured. Yersinia spp. was isolated in association with salmonella on three occasions, twice with rotavirus and once each with Shigella sonnei, Campylobacter jejuni and Trichuris trichiura.     

Epidemiologic investigation of a Yersinia camp outbreak linked to a food handler

In July 1981, an outbreak of gastroenteritis occurred at a summer diet camp. Of the 455 campers and staff, 35 per cent developed an illness characterized by abdominal pain, fever, diarrhea, and/or nausea and vomiting. A total of 53 per cent experienced abdominal pain. Seven persons were hospitalized, five of whom had appendectomies. Yersinia enterocolitica serogroup 0:8 was isolated from 37 (54 per cent) of 69 persons examined, including the camp cook and three assistants. An epidemiologic investigation demonstrated that illness was associated with consumption of reconstituted powdered milk and/or chow mein . Y. enterocolitica serogroup 0:8 was subsequently isolated from milk, the milk dispenser, and leftover chow mein . Information obtained during the investigation suggested that the Yersinia had been introduced by a food handler during food-processing procedures.     

进口冻肉中小肠结肠炎耶尔森氏菌检出情况分析

目的：了解我国进口冻肉产品中小肠结肠炎耶尔森氏菌的检出情况，为此类产品的风险分析和检验检疫工作提供依据。方法：通过采用小肠结肠炎耶尔森氏菌的国标检验方法和VITEK、API生化鉴定仪对247份进口冻肉产品进行检测。结果：247份样品中共检出耶尔森属菌33份，其中17份为小肠结肠炎耶尔森氏菌，检出率为6．88％，均属于生物1A型，其中3株为血清O：8型，其余均属非常见血清型。阳性样品中16份为冻鸡类样品，1份为冻猪肉类样品。94份海产样品无一份检出。结论：通过实验数据分析我国进口的冻肉产品中冻鸡类产品检出小肠结肠炎耶尔森氏菌比率较高，而海产品和冻猪肉产品中检出率相对较低，所以认为冻鸡类产品小肠结肠炎耶尔森氏菌污染风险较高，应加强此类产品检验监管力度。     

登封市屠宰场生猪小肠结肠炎耶尔森菌病原学研究

目的 了解登封市屠宰场生猪小肠结肠炎耶尔森菌带菌率、血清分型、毒力基因分布等情况,为制定预防措施提供参考依据。方法 从屠宰场生猪扁桃体及回盲部内容物中分离小肠结肠炎耶尔森菌,并进行生化鉴定、血清分型、毒力基因PCR检测。结果 从196份生猪咽拭子中分离出107株小肠结肠炎耶尔森菌,检出率为54.59%;从196份生猪肛拭子中分离出36株小肠结肠炎耶尔森菌,检出率为18.37%。检出菌血清型为O∶3,生物型为3型,Ⅰ型（ail＋、ystA＋、ystB-、yadA＋、virF＋）占93.71%（134/143）,Ⅱ型（ail＋、ystA＋、ystB-、yadA-、virF-）占6.29%（9/143）。结论 登封市生猪小肠结肠炎耶尔森菌以致病性菌株为主,今后应加强该菌的进一步监测工作。     

Contaminated roof-collected rainwater as a possible cause of an outbreak of salmonellosis.

Roof-collected rainwater is a common water source in subtropical regions and has not been associated with human illness. In Trinidad, the West Indies, a church group, attending a rural camp, developed gastrointestinal illness, caused by Salmonella arechevalata. This rare serotype was isolated from stool specimens of campers, foods eaten at the camp, and a water tap, which was supplied by a storage tank of roof-collected rainwater. The surface of the roof, used as water catchment, was covered with bird faeces. It is postulated that rainwater, falling on the roof, washed off animal excrement which contained S. arechevalata and led to the outbreak of salmonellosis through camper ingestion of contaminated food and water.     

Duration of carriage and transmission of Yersinia enterocolitica biotype 4, serotype 0:3 in dogs.

Human infections with pathogenic strains of Yersinia enterocolitica have been linked to contact with dogs excreting these microorganisms. This study examines the carriage and transmission of Y. enterocolitica biotype 4, serotype 03 in dogs. Fourteen 6-month-old cross-bred dogs were separated into 5 groups, 2 containing 4 dogs (I and II) and the others 2 dogs (III-V). Each of the 4 dogs in Group I and 2 of the dogs in Group II were inoculated orally with the test strain. Bacteriological examination of faecal samples showed that dogs can be readily infected and can carry the organism for up to 23 days. The two in-contact dogs in Group II started to shed the test organism after 5 days. Subsequent transfer of these dogs to Group III and those in Group III to Group IV showed that Y. enterocolitica biotype 4, serotype 03 can be readily transmitted between dogs. At no time did any of the dogs show clinical signs of infection. Group V served as a negative control for the trial. These findings suggest that dogs can carry Y. enterocolitica biotype 4, serotype 03 asymptomatically and hence might act as a potential source of infection for people.     

Association between clinical presentation, biogroups and virulence attributes of Yersinia enterocolitica strains in human diarrhoeal disease.

Traditionally the enteric pathogen Yersinia enterocolitica has been differentiated into biogroups. Despite being considered as non-pathogenic, biogroup 1A isolates have constituted a sizeable fraction of strains from patients with gastroenteritis in many reports. To establish a potential clinical significance for biogroup 1A isolates of Y. enterocolitica, clinical disease in patients with gastroenteritis excreting such isolates was compared with symptoms among patients found infected with pathogenic biogroups. Clinical data and isolates of 66 patients from whom Y. enterocolitica had been isolated by direct plating were available for study. There was an association between patient age below 3 years and infection with ''pathogenic'' Y. enterocolitica. The severity of gastroenteritis and other symptoms, however, did not depend on the biogroup, or the presence of the virulence plasmid in the yersinia strain isolated from the patients. Strains belonging to biogroup 1A of Y. enterocolitica showed two clusters of ribotypes, one of which encompassed most isolates recovered from humans, the other being associated with environmental isolates. This might indicate the existence of human-adapted and potentially pathogenic strains among biogroup 1A of Y. enterocolitica.     

Epidemiological data on pathogenic Yersinia enterocolitica in Southern Germany during 2000-2006

Yersinia enterocolitica is the most common species causing enteric yersiniosis, which is still the third most frequently reported foodborne gastroenteritis in Europe. Y. enterocolitica generally causes sporadic human infections, and outbreaks are rare. The most important infection source of yersiniosis is believed to be contaminated pork and pork products. Data on the prevalence of pathogenic Y. enterocolitica in animals and foodstuffs are very limited and old; thus, more information on the extent and range of the prevalence of this enteropathogen in nonhuman sources is needed. In this work, prevalence of pathogenic Y. enterocolitica in different sources in Bavaria is presented. Further, the antimicrobial resistance of human and nonhuman strains is reported. The highest isolation rate of pathogenic Y. enterocolitica (67%) was found in tonsils of slaughter pigs. No pathogenic strains were isolated from cattle, sheep, turkey, and horses. ail-Positive Y. enterocolitica was detected in dogs (5%), cats (3%), and rodents (3%) by real-time PCR. Pathogenic Y. enterocolitica was isolated only from raw pork, especially from edible offal (51%). Surprisingly, 38% of game was contaminated with this pathogen when the samples were studied with PCR. Additionally, some raw pork sausages and one poultry sample were PCR positive. All pathogenic Y. enterocolitica isolates from nonhuman sources were belonging to bioserotype 4/O:3. Antimicrobial resistance of 60 human and 140 porcine strains of bioserotype 4/O:3 was tested by the agar disc diffusion method to 15 different antimicrobial agents. All Y. enterocolitica 4/O:3 strains were susceptible to most of the tested antibacterial agents.     

Dengue fever, Hawaii, 2001-2002

Autochthonous dengue infections were last reported in Hawaii in 1944. In September 2001, the Hawaii Department of Health was notified of an unusual febrile illness in a resident with no travel history; dengue fever was confirmed. During the investigation, 1,644 persons with locally acquired denguelike illness were evaluated, and 122 (7%) laboratory-positive dengue infections were identified; dengue virus serotype 1 was isolated from 15 patients. No cases of dengue hemorrhagic fever or shock syndrome were reported. In 3 instances autochthonous infections were linked to a person who reported denguelike illness after travel to French Polynesia. Phylogenetic analyses showed the Hawaiian isolates were closely associated with contemporaneous isolates from Tahiti. Aedes albopictus was present in all communities surveyed on Oahu, Maui, Molokai, and Kauai; no Ae. aegypti were found. This outbreak underscores the importance of maintaining surveillance and control of potential disease vectors even in the absence of an imminent disease threat.     

Sources of sporadic Yersinia enterocolitica infections in Norway: a prospective case-control study.

Yersinia enterocolitica is a recognized cause of gastroenteritis in northern Europe. During October 1988-January 1990, a prospective case-control study was performed to address risk factors associated with sporadic Y. enterocolitica infections in southeastern Norway. Sixty-seven case-patients (mean age 23.4 years, range 8 months-88 years) and 132 age-, sex- and geographically-matched controls were enrolled in the study. Multivariate analysis of the data showed that persons with Y. enterocolitica infection reported having eaten significantly more pork items (3.79 v. 2.30 meals, P = 0.02) and sausage (2.84 v. 2.20 meals, P = 0.03) in the 2 weeks before illness onset than their matched controls; only one patient had eaten raw pork. Patients were also more likely than controls to report a preference for eating meat prepared raw or rare (47 v. 27%, P = 0.01), and to report drinking untreated water (39 v. 25%, P = 0.01) in the 2 weeks before illness onset. Each of these factors was independently associated with disease, suggesting a link between yersiniosis and consumption of undercooked pork and sausage products and untreated water. Efforts should be directed towards developing techniques to reduce Y. enterocolitica contamination of pork and educating consumers about (1) proper handling and preparation of pork items and (2) the hazards of drinking untreated water.     

Salmonella Typhimurium infections transmitted by chlorine-pretreated clover sprout seeds.

Raw seed sprouts have caused numerous outbreaks of enteric infections. Presoaking seeds in a 20,000 mg/liter (ppm) calcium hypochlorite solution before sprouting is recommended to reduce bacterial contamination and infection risk. In 1999, the authors investigated an outbreak of Salmonella serotype Typhimurium infections in Colorado. In a case-control study, they matched 20 cases with 58 controls by age, sex, and telephone prefix; 10 (52%) of 19 cases and no controls recalled eating raw alfalfa-style sprouts in the 5 days before the patient's illness (p < 0.00001). Traceback implicated clover sprouts grown from seeds shared by two sprouters. The time period and region over which these sprouts were sold matched the occurrences of 112 culture-confirmed illnesses. Only one of the sprouters presoaked seeds as recommended, and fewer infections were attributable to this sprouter (0.29 vs. 1.13 culture-confirmed infections/50-pound (110.1-kg) bag of seed). After recall of the implicated sprouts and seed, S. Typhimurium illnesses declined. Contaminated raw clover sprouts can cause outbreaks of enteric illness. Presoaking contaminated seeds in a 20,000 mg/liter calcium hypochlorite solution reduces, but does not eliminate, the risk of infection. Until safer production methods are developed, persons eating raw sprouts continue to risk developing potentially serious gastrointestinal illness.     

An outbreak of shigellosis at an outdoor music festival

In August 1988, an estimated 3,175 women who attended a 5-day outdoor music festival in Michigan became ill with gastroenteritis caused by Shigella sonnei. Onset of illness peaked 2 days after the festival ended, and patients were spread throughout the United States by the time the outbreak was recognized. An uncooked tofu salad served on the last day was implicated as the outbreak vehicle (odds ratio = 3.4, p less than 0.0001). Over 2,000 volunteer food handlers prepared the communal meals served during the festival. This large foodborne outbreak had been heralded by a smaller outbreak of shigellosis among staff shortly before the festival began and by continued transmission of shigellosis from staff to attendees during the festival. S. sonnei isolated from women who became ill before, during, and after the festival had identical antimicrobial susceptibility patterns and plasmid profiles. Limited access to soap and running water for handwashing was one of the few sanitary deficits noted at this gathering. This investigation demonstrates the need for surveillance and prompt public health intervention when Shigella infections are recognized in persons attending mass outdoor gatherings, the singular importance of handwashing in reducing secondary transmission of shigellosis, and the potential for explosive outbreaks when communal meals are prepared by large numbers of food handlers.     

Salmonella montevideo infections associated with salami products made with contaminated imported black and red pepper --- United States, July 2009-April 2010

In August and September 2009, PulseNet, the national molecular subtyping network for foodborne disease surveillance, detected a multistate cluster of Salmonella Montevideo infections with an indistinguishable pulse-field gel electrophoresis (PFGE) pattern (XbaI PFGE pattern JIXX01.0011). Cases were geographically dispersed, and the age and sex distributions were typical for reported Salmonella cases. Montevideo is the seventh most common Salmonella serotype in the United States; of 1,225 PFGE patterns in the PulseNet Montevideo database, the outbreak strain pattern is the most common. PulseNet monitored this pattern and detected an increase in the number of isolates in November 2009, leading CDC to begin coordinating a multistate investigation. This report summarizes the results of that investigation, which identified 272 cases from 44 states and the District of Columbia, with illness onset from July 1, 2009, to April 14, 2010. In a multistate case-control study, consumption of salami was associated with illness. Purchase information from membership card records helped determine specific brands of Italian-style meat products associated with cases. The outbreak strain was identified in salami products, one company A facility environmental sample, and sealed containers of black and red pepper used to produce company A salami products. This outbreak highlights the importance of preventing post-processing contamination of ready-to-eat products from raw ingredients such as spices.     

首次发现0:9血清型小肠结肠炎耶尔森氏菌引起的腹泻爆发流行

本文首次报告由0:9血清型、生物3型小肠结肠炎耶尔森氏菌引起的一起食物源性急性腹泻爆发流行。发病率为64.44%、病人的主要临床表现为腹痛(95.17%)、腹泻(56.25%)、头昏。头痛(53.40%)及发热(29.29%)。从33名病人粪便标本中分离出13株0:9血清型小肠结肠炎耶尔森氏菌。这些菌株具有典型的生化反应,大多数具有病原性。病人恢复期血清抗体滴度多在1:160以上。