Recurrent outbreaks caused by the same Salmonella enterica serovar Infantis clone in a German rehabilitation oncology clinic from 2002 to 2009.

BACKGROUND: Repeated outbreaks of salmonellosis caused by Salmonella enterica serovar Infantis at a rehabilitation clinic in Germany were investigated microbiologically from August 2002 to August 2009. AIM: To identify the sources of transmission and characterize the S. enterica serovar Infantis isolates. METHODS: Associated with these outbreaks, isolates from 98 patients, two kitchen staff, five food samples, four swabs of kitchen facilities, three samples of chicken faeces and one sample of sewage water were evaluated by phage typing. All S. enterica serovar Infantis isolates investigated (N=113) were related to phage type (PT) 29. Additionally, 44 of the 113 isolates were selected at random for typing by XbaI macrorestriction and pulsed-field gel electrophoresis (PFGE). FINDINGS: Typing of the 44 isolates showed that the recurrent infections were caused by the single clone PT 29/XB27+44 (42/44, 95.5%). The most likely route of transmission was only identified in the last outbreak in 2009 within the present study. It was found to be cross-contamination in the kitchen facilities (emanating from a contaminated wooden panel), in combination with carriers among the kitchen staff. CONCLUSIONS: This study demonstrated important details of hospital-specific epidemiological processes, and alludes to a long-term reservoir of an epidemic clone of S. enterica serovar Infantis either in a backyard flock of poultry or in an inanimate kitchen reservoir.

Outbreak of Salmonella Strathcona caused by datterino tomatoes, Denmark, 2011.

In September 2011, a patient cluster with a rare Salmonella serotype - Strathcona - was identified in Denmark. An outbreak investigation was initiated to reveal the source in order to stop the outbreak. In addition to hypothesis-generating interviews, comparable analyses of patients' household shopping receipts were conducted. A matched case-control study with 25 cases and 56 population register controls was conducted to test the findings of the hypothesis-generating investigation. In total, 43 cases of Salmonella Strathcona were reported in Denmark. Additionally, 28 cases were reported from Germany, Italy, Austria and Belgium. The results of the investigation in Denmark showed that 8/10 cases had bought datterino tomatoes prior to disease onset. Illness was associated with a specific supermarket chain [matched odds ratio (mOR) 16·9, 95% confidence interval (CI) 2·2-130], and having consumed elongated small tomatoes (OR 28·1, 95% CI 2·6-302). Traceback investigation showed that the tomatoes came from an Italian producer. This outbreak, linked to tomatoes, underpins the growing recognition of the broad source range of Salmonella and the ability of fresh produce to cause multi-country outbreaks. It is important to strengthen the international cooperation between public-health and food-safety authorities in the European Union to investigate future multi-country outbreaks in order to prevent illness from ready-to-eat produce.

A prolonged outbreak of Salmonella Infantis associated with pork products in central Germany, April-October 2013.

One of the largest and longest Salmonella outbreaks in Germany within the last 10 years occurred in central Germany in 2013. To identify vehicles of infection, we analysed surveillance data, conducted a case-control study and food traceback. We identified 267 cases infected with Salmonella Infantis with symptom onset between 16 April and 26 October 2013 in four neighbouring federal states. Results of our study indicated that cases were more likely to have eaten raw minced pork from local butcher's shops [odds ratio (OR) 2·5, 95% confidence interval (CI) 1·1-5·8] and have taken gastric acid-reducing or -neutralizing medication (OR 3·8, 95% CI 1·3-13) than controls. The outbreak was traced back to contaminated raw pork products found in different butcher's shops supplied by one slaughterhouse, to pigs at one farm and to an animal feed producer. Characterization of isolates of human, food, animal, feed, and environmental origin by phage-typing and pulsed-field gel electrophoresis confirmed the chain of infection. Insufficient hygiene standards in the slaughterhouse were the most probable cause of the ongoing transmission. We recommend that persons taking gastric acid suppressants should refrain from consuming raw pork products. Improving and maintaining adequate hygiene standards and process controls during slaughter is important to prevent future outbreaks.

Epidemiological analysis of the dynamic and diversity of Salmonella spp. in five German pig production clusters using pheno- and genotyping methods: an exploratory study.

An exploratory study in five conventional pig production clusters was carried out to investigate the dynamic and diversity of Salmonella spp. within different production stages and sample site categories (pooled feces, direct and non-direct environment). Observing two production cycles per production cluster, a total of 1276 samples were collected along the pig production chain. Following a microbiological examination via culture, 2246 subcultures were generated out of 285 Salmonella positive samples and analysed by pheno- and genotyping methods. Based on a combination of serotyping, MLVA (multiple-locus variable-number tandem repeat (VNTR) analysis), PFGE (pulse-field gel electrophoresis) and MLST (multilocus sequence typing), an amount of 22.3% Salmonella positive samples were characterized in clonal lineages and its variants. Within each production cluster, one main clonal lineage could be identified and persisted over both production cycles with a large diversity of variants and a wide distribution in sample site categories and production stages. Results underline the importance of biosecurity with emphasis on the environment to prevent persistence and circulation of Salmonella within herds. Furthermore, the combined implementation of MLVA, PFGE and MLST with conventional culture techniques for isolate classification could be successfully applied as an effective and valuable tool for identifying similar pattern of Salmonella occurrence within pig production clusters.

Multidisciplinary investigation of a multicountry outbreak of Salmonella Stanley infections associated with turkey meat in the European Union, August 2011 to January 2013.

Between August 2011 and January 2013, an outbreak of Salmonella enterica serovar Stanley (S. Stanley) infections affected 10 European Union (EU) countries, with a total of 710 cases recorded. Following an urgent inquiry in the Epidemic Intelligence Information System for food- and waterborne diseases (EPIS-FWD) on 29 June 2012, an international investigation was initiated including EU and national agencies for public health, veterinary health and food safety. Two of three local outbreak investigations undertaken by affected countries in 2012 identified turkey meat as a vehicle of infection. Furthermore, routine EU monitoring of animal sources showed that over 95% (n=298) of the 311 S. Stanley isolates reported from animal sampling in 2011 originated from the turkey food production chain. In 2004­10, none had this origin. Pulsed-field gel electrophoresis (PFGE) profile analysis of outbreak isolates and historical S. Stanley human isolates revealed that the outbreak isolates had a novel PFGE profile that emerged in Europe in 2011. An indistinguishable PFGE profile was identified in 346 of 464 human, food, feed, environmental and animal isolates from 16 EU countries: 102 of 112 non-human isolates tested were from the turkey production chain. On the basis of epidemiological and microbiological evidence, turkey meat was considered the primary source of human infection, following contamination early in the animal production chain.

An outbreak of Salmonella Newport associated with mung bean sprouts in Germany and the Netherlands, October to November 2011.

The largest Salmonella enterica serovar Newport outbreak (n=106) ever reported in Germany occurred in October and November 2011. Twenty associated cases were reported in the Netherlands. The outbreak investigation included an analytical epidemiological study, molecular typing of human and food isolates and food traceback investigations. Unspecified Salmonella had been detected in samples of mung bean sprouts at a sprout producer (producer A) in the Netherlands and mung bean sprouts contaminated with S. Newport had been found during routine sampling at a sprout distributor in Germany. Therefore, we tested the hypothesis of sprouts being the infection vehicle. In a case-control study, we compared 50 notified adult S. Newport cases with 45 Salmonella enterica serovar Enteritidis cases regarding their food consumption in the three days before illness. In multivariable logistic regression analysis, only sprout consumption was significantly associated with S. Newport infection (odds ratio: 18.4; 95% confidence interval: 2.2-150.2). Molecular typing patterns of human isolates were indistinguishable from a mung bean sprouts isolate. Traceback of sprouts led to distributors and producer A in the Netherlands. Since sprouts are frequently contaminated with microorganisms, consumers need to be aware that consumption of raw or insufficiently cooked sprouts may pose a health risk.

Typing of Salmonella enterica serovar Infantis isolates from 51 outbreaks in Germany between 1974 and 2009 by a novel phage-typing scheme.

We developed a new phage-typing method and evaluated its application in combination with XbaI macrorestriction analysis by pulsed-field gel electrophoresis (PFGE) as a useful tool for the long-term epidemiology of Salmonella enterica serovar Infantis. In this study, we investigated 1008 S. Infantis isolates recovered from humans, various animal species and food products from 1973 to 2009. The typing scheme is based on 17 typing phages, defining 61 different patterns within the strain collection. The experiments showed that phage typing is a reliable method for differentiation of outbreaks and sporadic clinical cases as well as for elucidation of chains of transmission. The combined analysis of phage typing and PFGE revealed the existence of epidemic clones with a high stability over time like PT29/XB27 which was identified in nosocomial salmonellosis, community outbreaks as well as in broiler chickens from 2002 to 2009.

Evidence for the transmission of Salmonella from reptiles to children in Germany, July 2010 to October 2011.

This study examines the Salmonella status in reptiles kept in households with children suffering from gastroenteritis due to an exotic Salmonella serovar, to obtain information on possible transmission paths. A number of affected households (n=79) were contacted, and almost half (34/79) comprised at least one reptile in the home. Of the households, 19 were further studied, whereby a total of 36 reptiles were investigated. Samples were taken from the reptiles including the oral cavity, the cloaca, the skin and, in the case of lizards, the stomach, and isolation of Salmonella strains was performed using repeated enrichment and typing. Where the Salmonella serovars of the infected child and the reptile were identical, typing was followed by pulsed-field gel electrophoresis (PFGE). Bearded dragons (Pogona vitticeps) constituted 19 of 36 examined reptiles. Altogether 319 Salmonella isolates were investigated and 24 different serovars identified in the reptiles. In 15 of 19 households, an identical serovar to the human case was confirmed in at least one reptile (including 16 of all 19 bearded dragons examined). The results demonstrate that reptiles and especially bearded dragons shed various Salmonella serovars including those isolated from infected children in the respective households. Hygiene protocols and parents' education are therefore highly necessary to reduce the risk of transmission. From a terminological point of view, we propose to call such infections 'Reptile-Exotic-Pet-Associated-Salmonellosis' (REPAS).

[Broncho-pulmonary salmonellosis--a case series and review of the literature]. / Die bronchopulmonale Salmonellose--eine Fallserie und Literaturübersicht.

Broncho-pulmonary salmonelloses are rare manifestations of extraintestinal focal infections in adults caused by different subspecies of Salmonella. They may appear without previous gastroenteritic symptoms especially in patients older than 60 years, as well as in patients who are immunocompromised or suffer from chronic pulmonary diseases. The transmission route is hematogenous or via aspiration of contaminated gastric fluid. Complications are acute respiratory distress syndrome, lung abscesses and pleural empyemas. Complicated und lethal courses have been described frequently. Therefore, antibiotic therapy should be initiated in every case with sufficient duration of treatment and in accordance to antibiotic resistance. Recommended antibiotics are third generation cephalosporins, trimethoprim-sulfamethoxazole, ampicillin or fluoro-quinolones. In this review 4 different clinical courses of broncho-pulmonary salmonellosis caused by Salmonella enterica subsp. enterica serovar Brandenburg, Salmonella groups B (O4), C (O6) and O11 to O67 are presented and discussed in the context of the current literature.

Subtype specific risk factor analyses for sporadic human salmonellosis: a case-case comparison in Lower Saxony, Germany.

With the intention to deepen the knowledge of the vertical transmission of particular subtypes of Salmonella enterica from "the stable to the table" a case1-case2 analysis in Lower Saxony, Germany, was conducted. The data collection was based on standardised telephone interviews with 1741 Salmonella case persons. Single-factor-analyses revealed statistically significant associations between S. Typhimurium infections and animal keeping (odds ratio (OR): 1.4; 95%-Confidence-interval (CI): 1.2-1.7), especially rodents (OR 1.5; CI 1.2-2.1), and with consumption of meat (OR 1.9; CI 1.3-2.8), raw ground pork (OR 3.0; CI 2.1-4.2) and uncooked pork sausage (OR 2.1; CI 1.6-2.9). The S. Typhimurium phage type DT 104 was associated most with consumption of uncooked pork sausage (OR 3.6; CI 1.3-8.5). Multiple logistic regression analyses confirmed the associations between S. Typhimurium infection and consumption of raw ground pork and with animal contact. The results circumstantiate the assumption of raw pork products still being a relevant source for S. Typhimurium infections in Germany. Therefore, it is recommended to intensify efforts to reduce salmonella infections caused by raw pork products. S. Enteritidis infection was associated statistically significantly with travelling abroad (OR 2.1; CI 1.6-3.3), consumption of raw tomatoes (OR 1.8; CI 1.5-2.1), dried herbs (OR 2.1; CI 1.0-1.8), and undercooked eggs (OR 1.3; CI 1.1-1.6) compared with other serovars. These results were confirmed in multiple logistic regression analyses, as well.

Severe infections caused by Salmonella Enteritidis PT8/7 linked to a private barbecue.

A cohort study on a barbecue-associated Salmonella outbreak was conducted to describe the burden of disease and to identify the outbreak vehicle. Dose-response relationships were tested with Fisher's exact and Wilcoxon rank sum tests (alpha = 0·05). S. Enteritidis isolates were cultured and phage-typed. Information was available for 11 out of 14 individuals attending the barbecue; all were healthy young adults (median age 27 years). The attack rate was 100%. Three cases were hospitalized and two developed acute pancreatitis. The exposure common to all cases was a vegetable pasta salad that had been stored unrefrigerated for 23 h. Consuming higher doses was associated with longer median symptom duration (7 days vs. 4 days, P = 0·11). S. Enteritidis was found in the stools of nine barbecue guests. Phage type 8/7 was identified in the stools of the salad preparer and one barbecue guest. This outbreak shows that S. Enteritidis can cause serious infection in young healthy individuals without well-known risk factors.

Investigation of an excess of Salmonella enteritidis phage type 14b and MLVA type 4-7-3-13-10-2-2 in Luxembourg, Belgium and Germany during 2010.

We investigated an increase of human cases of Salmonella Enteritidis occurring from August until November 2010 in Belgium, Luxembourg and Germany involving an estimated three hundred laboratory confirmed cases. Molecular typing indicated that the increase in Luxembourg and Belgium was due a particular strain having phage type 14b, MLVA pattern 4-7-3-13-10-2-2 and fully susceptible to the Enternet panel of antibiotics. MLVA and phage typing were found to have similar discriminatory power on a collection of 40 Belgian and Luxembourg strains isolated during 2010. Epidemiological investigations in Luxembourg suggested eggs as a possible source for some cases, although supermarket eggs tested were negative. No other EU countries observed a substantial increase of cases, although three smaller outbreaks in Germany were also due to a strain with the same phage type and MLVA pattern. In 2010 the EU directive banning battery cages came into force in Germany followed by a dioxin food scare incident. Given that the EU Laying Hens Directive will come into force across all Member States in 2012, a closer monitoring of Salmonella contamination of imported eggs at retail and wholesale level is recommended.

Outbreak of Salmonella Montevideo associated with a dietary food supplement flagged in the Rapid Alert System for Food and Feed (RASFF) in Germany, 2010.

In March 2010 the Rapid Alert System for Food and Feed (RASFF) was used to inform about Salmonella Montevideo in a herbal food supplement, formulated in capsules, distributed under a Dutch label in Germany. Simultaneous to the first RASFF notice, in the last two weeks of March 2010 an unusual number of 15 infections with S. Montevideo was notified within the electronic reporting system for infectious diseases at the Robert Koch Institute. Adult women (median age: 43, range: 1-90 years) were mainly affected. An outbreak was suspected and the food supplement hypothesised to be its vehicle. Cases were notified from six federal states throughout Germany, which required efficient coordination of information and activities. A case-control study (n=55) among adult women showed an association between consumption of the specific food supplement and the disease (odds ratio (OR): 27.5, 95% confidence interval (CI): 3.1-infinity, p-value=0.002). Restricting the case-control study to the period when the outbreak peaked (between 29 March and 11 April 2010) resulted in an OR of 43.5 (95% CI: 4.8-infinity, p-value=0.001). Trace-back of the supplement's main ingredient, hemp seed flour, and subsequent microbiological testing by pulsed-field gel electrophoresis supported its likely role in transmission. This outbreak investigation illustrates that information from RASFF may aid in hypothesis generation in outbreak investigations, though likely late in the outbreak.

[Reptile-associated Salmonellosis in Infants in Germany]. / Reptilien-assoziierte Salmonelleninfektionen bei Säuglingen und Kleinkindern in Deutschland.

Salmonellosis is an important disease in childhood. Increasing infections caused by meat and raw egg consumption starts in the second year of life. The transmission from reptiles to infants is an alternative route. Reptile-associated salmonellosis is becoming more significant for pediatricians and microbiologists due to the increasing numbers of household exotic pets. Investigations of routes of infections in connection with the local health authorities including microbiological, serological and molecular biological tests is possible in case of atypical salmonellosis. During recent years (2006-2008) an increasing number of salmonellosis cases caused by reptiles. Most of the 26 patients were infants of less than one year of age. Also Salmonella strains of subspecies II, IIIa, IIIb and IV play an important role. The US Centers for Disease Control and Prevention (CDC) has published recommendations which includes washing hands with soap and water after handling reptiles or the cages and keeping reptiles out of food preparation areas. The CDC has also adviced that children less than five years should not have reptiles as pets.

[Reptile-associated Salmonellosis in a Breastfed Infant]. / Reptilien-assoziierte Salmonellenenteritis bei einem voll gestillten Säugling.

BACKGROUND: Although salmonellosis is one of the most common childhood illnesses associated with enteric bacteria, breastfed babies do not often get infected with Salmonella. In such cases it is therefore necessary to look carefully for the source of infection. PATIENT: It is reported an 8-week-old female infant with acute haemorrhagic diarrhoea and fever. With symptomatic therapy and breast-feeding her condition improved without antibiotic therapy. Microbiological diagnosis and subtyping identified infection with Salmonella enterica serovar Pomona. The source of the infection was a bearded dragon ( Pogona SPP.) living in a neighborhood household. Monitoring of the child showed shedding of the bacterium over a nine month period. CONCLUSION: In all cases of salmonellosis in breastfed babies, the source of infection should be carefully determined. Small numbers of bacteria can cause a symptomatic infection in this age group. Therefore an intensive search of the transmission route is indicated to develop prevention strategies.

[Protracted nosocomial outbreak of Salmonella Enteritidis LT 8/7]. / Protrahiert verlaufender nosokomialer Ausbruch von Salmonella Enteritidis LT 8/7.

INTRODUCTION: In spring 2007a cluster of nosocomial salmonellosis cases, culture confirmed for SALMONELLA Enteritidis lysotype (LT) 8/7, occurred in a Wolfsburg hospital. An outbreak investigation was initiated to determine the epidemiology of the outbreak and to identify and control the possible sources. METHODS: A multidisciplinary outbreak team was formed including members from hospital hygiene and local, state and national health and veterinarian authorities. Active surveillance was set up in the hospital to find new cases. A retrospective case control study was conducted to identify possible risk factors for disease. Hospital workers and food samples were tested for the pathogen and positive isolates were typed. RESULTS: Between calendar weeks 4 and 24 of the year 2007, a total of 28 patients with a median age 66 years had nosocomial salmonellosis culture confirmed for SALMONELLA Enteritidis LT 8/7. In food samples from February, the same Salmonella lysotype was isolated in 4 different food samples. SALMONELLA Enteritidis LT 8/7 was also identified in stool samples from 5 kitchen personnel. The case control study indicated antacida therapy (odds ratio: 5.5, 95 % CI 1.2 - 26.0) as a risk factor for nosocomial salmonellosis among patients. No particular diet was associated with an increased risk of disease. DISCUSSION: This nosocomial salmonellosis outbreak was characterised by prolonged duration and a low infection rate among patients. The epidemiological investigation suggests that the origin of the outbreak was food that was probably associated with a contamination in the hospital kitchen. Furthermore, kitchen staff could, as carriers, have contributed to a low-level contamination of various foods for a long period. The intermittent occurrence of the cases is best explained by a low level of contaminated food which primarily led to clinical symptoms among especially vulnerable persons (older patients with antacida therapy). Considering the unusual progression of this outbreak, hospitals should initiate an intensive epidemiological and microbiological investigation, even if only few nosocomial salmonellosis cases occur.

Salmonella infections associated with reptiles: the current situation in Europe.

Salmonella infections are caused by consumption of contaminated food, person-to-person transmission, waterborne transmission and numerous environmental and animal exposures. Specifically, reptiles and other cold blooded animals (often referred to as "exotic pets") can act as reservoirs of Salmonella, and cases of infection have been associated with direct or indirect contact with these animals. Approximately 1.4 million human cases of Salmonella infection occur each year in the United States and it has been estimated that 74,000 are a result of exposure to reptiles and amphibians. Regular case reports of reptile-associated salmonellosis in the US are available for the period 1994-2002. Cases of Salmonella infection attributed to direct or indirect contact with reptiles or other exotic pets have been described in a number of European countries, too but a more comprehensive overview of the magnitude of this problem in Europe is lacking. In total, 160,649 human cases of salmonellosis were reported in 2006 in the then 25 European Union Member States, Bulgaria, Romania, Iceland, Liechtenstein and Norway.

Outbreaks of monophasic Salmonella enterica serovar 4,[5],12:i:- in Luxembourg, 2006.

A monophasic Salmonella enterica serovar 4,[5],12:i:- phage type DT193 emerged as the dominant serovar in Luxembourg in 2006, when it caused two major outbreaks involving 133 laboratory-confirmed human cases, 24 hospitalisations, and one death. The outbreak strain had an uncommon pulsed-field gel electrophoresis pattern STYMXB.0031 and antibiotic resistance profile ASSuT. A high proportion of cases were clustered in institutions for the elderly and in day-care centers. Strains identical to the outbreak strain were recovered from two control meals, a nappy changing table, retail sausages and caecal porcine samples at an abattoir. Locally produced pork meat is strongly suspected to have been the vehicle for the outbreaks, although the precise mechanisms remain unclear.

[Cholangitis with hepatic microabscesses caused by Salmonella enterica serovar choleraesuis]. / Cholangitis mit hepatischen Mikroabszessen durch Salmonella enterica Serovar Choleraesuis.

HISTORY AND ADMISSION FINDINGS: A 71-year-old man was admitted to the emergency unit of another hospital with a mild gastroenteritis and high fever. On admission g-GT and C-reactive protein (CRP) levels were markedly elevated. Under nonspecific antibiotic therapy with ampicillin/sulbactam the fever persisted and for the first time, on day 5, the patient complained of right-sided abdominal pain. An increase in the laboratory values indicated cholestasis. After changing the antibiotics to ceftriaxon and metronidazole, acute cholangitis being suspected, the fever subsided immediately and the CRP level decreased. The patient was discharged after seven days of antibiotic treatment. But he was once more admitted after four weeks to another hospital because of severely reduced general condition and mild fever. He was transferred to our unit after two weeks. INVESTIGATIONS AND DIAGNOSIS: The test values indicated cholestasis and CRP was markedly elevated, while aminotransferase activity was slightly increased and normocytic normochromic anemia developed. Viral hepatitis, autoimmune and metabolic liver diseases, toxic liver damage, extrahepatic cholestasis and an endocarditis were excluded. Bile was aspirated by endoscopic retrograde cholangiopancreatography and added to blood culture bottles. Salmonella enterica serovar choleraesuis var. Kunzendorf was isolated. TREATMENT AND FURTHER COURSE: The patient was treated with ciprofloxacin, 2 x 250 mg by mouth for a total of five weeks. After 17 days of treatment no Salmonella bacteria were grown from a newly aspirated bile sample and the patient became free of fever. CONCLUSION: Salmonella infections do not always present as gastroenteritis. Bacteremia should be considered in the differential diagnosis of such infections. If cholangitis persists, the aspiration of bile for microbiological tests can be a rational diagnostic step and facilitates treatment. Prolonged administration of antibiotics is necessary to avoid relapse. and follow-up is very important when treatment is finished.