Outbreak Of Shigella Sonnei Infection Research Articles

Outbreak of Shigella sonnei infection in Terme City, Turkey, September 2012

Outbreak of Shigella sonnei infection in Terme City, Turkey, September 2012

Outbreak of Shigella sonnei infection in Norway linked to consumption of fresh basil, October 2011

We report a Shigella sonnei outbreak of 46 cases that occurred in Norway during October 2011. Two municipalities were involved. A large cluster (42 cases)was concentrated in north Norway, while a smallcluster (4 cases) occurred in the south-east region.Epidemiological evidence and trace back investigations have linked the outbreak to the consumption of imported fresh basil. The product has been withdrawn from the market. No further cases have been reported since 25 October.

A school outbreak of Shigella sonnei infection in China: Clinical features, antibiotic susceptibility and molecular epidemiology

To describe the clinical features of infection, and the antibiotic susceptibility of epidemic strains, and investigate plasmid maps and integrons of the isolates from an outbreak of Shigella sonnei infection at an elementary school in southwest China. Cross-sectional study. An elementary school and five hospitals in Chengdu in southwest China. There were 1,134 students in the school. 937 (82.6%) students had signs and symptoms. Of the 568 (60.6%, 568/937) hospitalized students, 93.3% 86.8%, 72.4%, and 28.9% of the hospitalized patients had diarrhea, fever, abdominal pain, and vomiting, respectively. S. sonnei strains were isolated from the stool samples of 36.0% (337/937) students. All of the outbreak isolates had the same high-level antimicrobial resistance and plasmid profiles, which were different from that of sporadic strains. All the outbreak S. sonnei isolates were positive for the integrin gene and contained class 2 integron; however, two outbreak isolates contained class 1 and class 2 integrons. Diarrhea, fever, and abdominal pain were the three most common clinical manifestations observed in patients infected with S. sonnei. High-level antibiotic resistance was observed among Shigella species.

Outbreak of Shigella sonnei infections in the Orthodox Jewish community of Antwerp, Belgium, April to August 2008

In the beginning of April 2008 three cases of Shigella sonnei infection were identified among the Orthodox Jewish community of Antwerp, Belgium. We conducted a descriptive study and a household cohort study to identify potential risk factors. Stool samples were cultured and antibiotic susceptibility of the isolates was determined. Between April and August 2008, 42 cases were registered. All characterised isolates (n=20) shared an identical pulsed-field gel electrophoresis profile and were indistinguishable from one of the twelve main strains detected in Israel in 2008, where the index case's father had stayed before the outbreak. The secondary attack rate in households was 8.5% (95% confidence interval (CI): 4.3–12.7). Multivariate analysis identified the following risk factors for secondary spread: households with more than three children (adjusted relative risk (RR): 9.17; 95% CI: 1.21–69.13), children younger than five years (adjusted RR: 5.45; 95% CI: 2.44–12.62), and children younger than 12 years assisting in washing younger siblings (adjusted RR: 5.45; 95% CI: 2.44–12.17). Rigorous hand washing, use of disposable towels, information for parents and caregivers, and exclusion of symptomatic children from day care, preschool and school for a minimum of 48 hours were implemented.

Shigella sonnei infections in Norway associated with sugar peas, May-June 2009.

In May 2009, the Norwegian Institute of Public Health (NIPH) identified a possible outbreak of Shigella sonnei infection involving four cases. Additionally, five suspected cases in two separate households were reported. Inspectors from the Norwegian Food Safety Authority (NFSA) visited the two households and found an unopened package of sugar peas imported from Kenya in one of the households. One sample from the sugar peas was positive for Shigella sonnei by two PCR methods. Based on this result and information from patient interviews, the NFSA prohibited all sales of sugar peas imported from Kenya.

Imported fresh sugar peas as suspected source of an outbreak of Shigella sonnei in Denmark, April-May 2009.

We report on an outbreak of Shigella sonnei infections involving ten cases notified through the laboratory surveillance system in Denmark in April and May. The likely source was consumption of fresh, raw sugar peas (sugar snaps) imported from Africa. This conclusion was based on interviews with cases and on the occurrence of a similar outbreak one month later in Norway. Fresh imported produce may occasionally be contaminated with pathogenic bacteria even when sold as ready-to-eat.

Outbreaks ofShigella sonneiinfections in Denmark and Australia linked to consumption of imported raw baby corn

We investigated an outbreak of Shigella sonnei infections in Denmark and Australia associated with imported baby corn from one packing shed in Thailand. We reviewed nationwide surveillance and undertook case finding, food trace-back and microbiological investigation of human, food and environmental samples. A recall of baby corn and sugar snaps was based on descriptive epidemiological evidence. In Denmark, we undertook a retrospective cohort study in one workplace. In total, 215 cases were laboratory-confirmed in Denmark, and 12 in Australia. In a multivariable analysis, baby corn was the only independent risk factor. Antibiotic resistance and PFGE outbreak profiles in Denmark and Australia were indistinguishable, linking the outbreaks. Although we did not detect S. sonnei in baby corn, we isolated high levels of other enteric pathogens. We identified a packing shed in Thailand that supplied baby corn to Denmark and Australia, and uncovered unhygienic practices in the supply chain. This outbreak highlights the importance of international communication in linking outbreaks and pinpointing the source.

International foodborne outbreak ofShigella sonneiinfection in airline passengers

During 22-24 August 2004, an outbreak of Shigella sonnei infection affected air travellers who departed from Hawaii. Forty-seven passengers with culture-confirmed shigellosis and 116 probable cases who travelled on 12 flights dispersed to Japan, Australia, 22 US states, and American Samoa. All flights were served by one caterer. Pulsed-field gel electrophoresis of all 29 S. sonnei isolates yielded patterns that matched within one band. Food histories and menu reviews identified raw carrot served onboard as the likely vehicle of infection. Attack rates for diarrhoea on three surveyed flights with confirmed cases were 54% (110/204), 32% (20/63), and 12% (8/67). A total of 2700 meals were served on flights with confirmed cases; using attack rates observed on surveyed flights, we estimated that 300-1500 passengers were infected. This outbreak illustrates the risk of rapid, global spread of illness from a point-source at a major airline hub.

Cross-border investigation of a Shigella sonnei outbreak in a group of Norwegian tourists after a trip to Russia

In early September 2006, the Norwegian Institute of Public Health was alerted to an outbreak of Shigella sonnei infections (shigellosis) among 23 Norwegian passengers who had taken a bus tour from Kirkenes, Norway to Murmansk, Russia. The trip lasted from 27 to 31 August, and the group stayed in various hotels and visited several restaurants in both Kirkenes and Murmansk during this period. Stool samples from three ill passengers yielded S. sonnei; an additional 10 passengers had gastrointestinal symptoms with diarrhoea or loose stools with abdominal pain. An investigation was initiated in collaboration with the department of epidemiological surveillance in Murmansk. We sent a questionnaire to the work e-mail addresses of all passengers asking about symptoms and exposures. Two restaurants and a hotel visited by the Norwegian tourists in Murmansk were inspected and sampled. Of all the food and beverage items mentioned in the questionnaire, only cured meat consumed in restaurant A in Murmansk on 28 August was associated with the risk of developing illness. Inspections of the restaurants in Murmansk identified some hygienic shortcomings and inadequate routines. However, S. sonnei could not be isolated from food samples or the personnel. Improved routines were implemented.

Waterborne epidemic outbreak of Shigella sonnei gastroenteritis in Santa Maria de Palautordera, Catalonia, Spain.

In August 2002 an outbreak of Shigella sonnei infection occurred in a Spanish town of 6343 inhabitants. In total, 756 people developed acute gastroenteritis and 181 cases were shigella-confirmed. The peak incidence was during 5-6 August 2002. The estimated primary attack rate was 9.97%; the attack rate for secondary cases was 38%. The <15 years ago group was most affected (16.49%). The town and its surroundings were served by two water systems, A and B. The cases had consumed water provided by system A (attack rate 164 cases/1000 population). Microbiological analysis of water from system A did not show the presence of coliform bacteria or shigella. This shigellosis outbreak was the largest reported in Spain. The impact of the epidemic was probably greater than the incidence detected.

A Multi‐Prefectural Outbreak of Shigella sonnei Infections Associated with Eating Oysters in Japan

Among roughly one thousand incidents of shigellosis annually in Japan, approximately 70% of the cases are estimated to be associated with overseas travel. However, at the end of 2001, reports of domestically acquired Shigella sonnei infections suddenly increased. We report here the first multi-prefectural outbreak of Shigella sonnei infections linked to the consumption of imported oysters in Japan at the end of 2001. Isolates of S. sonnei from patients epidemiologically linked to eating contaminated oysters and from the imported oysters themselves showed an indistinguishable pulsed-field gel electrophoresis pattern and drug resistance pattern.

Application of a geographic information system to the tracking and control of an outbreak of shigellosis.

A personal computer-based commercial geographic information system (GIS) was applied to an outbreak of Shigella sonnei infection at Fort Bragg, North Carolina. We used a database consisting of demographic, temporal, and home-address information for all recognized cases of S. sonnei that occurred among health care beneficiaries from 23 May 1997 through 14 August 1997. We imported this database into the GIS, which contained a digitized basemap of the local community. Through simultaneous examination of temporal and spatial distribution of the 59 identified cases of S. sonnei, a focus of infection in a single housing area was identified. Targeted education among residents of the neighborhood in which there was intense transmission was associated with prompt extinction of the epidemic. A GIS offers an efficient and practical way to directly visualize the dynamics of transmission of infectious diseases in the setting of a community outbreak.

A prolonged outbreak of Shigella sonnei infections in traditionally observant Jewish communities in North America caused by a molecularly distinct bacterial subtype.

During 1994-1996, Shigella sonnei outbreaks occurred in 8 North American traditionally observant Jewish communities. These communities remain relatively separate from neighboring populations while maintaining close contact by travel with coreligionists in other cities. Epidemiologic investigations suggested community-to-community transmission via travel. Outbreak-related and control isolates of S. sonnei from each city were subtyped by pulsed-field gel electrophoresis (PFGE) to confirm an epidemiologic linkage between outbreaks. Forty-three (94%) of 46 outbreak-related isolates had closely related PFGE patterns, constituting a single subtype; 33 (94%) of 35 control isolates demonstrated unrelated PFGE patterns. Several patterns differing by < or = 3 bands were identified within the outbreak subtype; one of these accounted for 65% of outbreak isolates. Hence, a single subtype of S. sonnei caused an international outbreak involving 8 traditionally observant Jewish communities, but not neighboring populations, over a 2-year period, suggesting sustained propagation of the epidemic strain between communities.

Communitywide shigellosis: control of an outbreak and risk factors in child day-care centers.

The study's objectives were to assess (1) control of a community outbreak of shigellosis through the promotion of handwashing, (2) risk factors in day-care centers, and (3) shigellosis attributable to attendance at a day-care center. In 1991, an outbreak of Shigella sonnei infections occurred in Lexington-Fayette County, Ky; 14 licensed child day-care centers were involved. Communitywide promotion of hand washing was instituted along with diarrhea surveillance. A case-control study compared day-care centers that had confirmed cases of shigellosis with centers that had none. A family transmission study determined those cases attributable to attendance at day-care centers. The outbreak abated 3 weeks after the interventions' initiation. Day-care centers with outbreaks were more likely than those with no cases to have a food handler who changed diapers and to provide transportation for children from their homes to the center. These centers also had a higher toddler-to-toilet ratio than control centers (21 vs 12). In 58% of families with shigellosis, the first person with diarrhea during the outbreak was a child younger than 6 years; 92% of diarrheal illnesses among these children were attributable to day-care attendance. Community involvement in increasing hand washing most likely resulted in control of this shigellosis outbreak. Diarrhea prevention strategies in day-care centers could prevent substantial communitywide disease.

An outbreak of Shigella sonnei infection associated with consumption of iceberg lettuce.

An outbreak of Shigella sonnei infection associated with consumption of iceberg lettuce.

Outbreak of Shigella sonnei infection traced to imported iceberg lettuce.

In the period from May through June 1994, an increase in the number of domestic cases of Shigella sonnei infection was detected in several European countries, including Norway, Sweden, and the United Kingdom. In all three countries epidemiological evidence incriminated imported iceberg lettuce of Spanish origin as the vehicle of transmission. The outbreaks shared a number of common features: a predominance of adults among the case patients, the presence of double infections with other enteropathogens, and the finding of two dominant phage types among the bacterial isolates. In Norway 110 culture-confirmed cases of infection were recorded; more than two-thirds (73%) were adults aged 30 to 60 years. A nationwide case-control study comprising 47 case patients and 155 matched control individuals showed that the consumption of imported iceberg lettuce was independently associated with an increased risk of shigellosis. Epidemiological investigation of a local outbreak incriminated iceberg lettuce from Spain, consumed from a salad bar, as the source. The presence of shigellae in the suspected food source could not be documented retrospectively. However, high numbers of fecal coliforms were detected in iceberg lettuce from patients' homes. Three lettuce specimens yielded salmonellae. The imported iceberg lettuce harbored Escherichia coli strains showing resistance to several antimicrobial agents, including ampicillin, ciprofloxacin, gentamicin, and trimethoprim-sulfamethoxazole. During the outbreak it is likely that thousands of Norwegians and an unknown number of consumers in other countries were exposed to coliforms containing antibiotic resistance genes.

An outbreak of Shigella sonnei infection due to contamination of a municipal water supply in Northern Israel

An epidemic of more than 8000 cases of Shigella sonnei infection took place in four adjacent urban communities which share the same water supply. The epidemic was caused by massive faecal contamination of the drinking water due to a leak from a broken main sewage pipe into an adjacent drilled well. The infecting organism in most cases was S. sonnei colicine type 6, biotype A, which showed a high rate of multiple resistance to commonly used antibacterial drugs. Most of those affected were children less than 15 years of age. Among adults the attack rates were higher in women. Most cases were mild, only 91 patients being admitted to hospital. One 5-year-old child died.

An outbreak of shigellosis associated with the consumption of raw oysters.

We describe an outbreak of Shigella sonnei infection among 24 persons who had eaten raw oysters in restaurants in southeastern Texas within five days before the onset of symptoms. The oysters in all eight restaurants were supplied by the same dealer, but examination of a routine water sample collected six days before the probable time of contamination showed the waters where the oysters were harvested to be free of fecal contamination, making widespread sewage contamination unlikely. The suspect oysters were traced to a single boat. Stool swabs from that boat's oyster harvesters allowed the identification of one asymptomatic carrier who had a strain of S. sonnei (determined by colicin typing, plasmid analysis, and testing for susceptibility to antibiotics) that was similar to or the same as that infecting the patients. Although the source of this man's infection was unknown, he reported having eaten no oysters. Investigation revealed that 5-gallon (19-liter) pails were used as toilets aboard the oyster boats. Sewage collected in these pails was often dumped overboard into the harvesting area. We conclude that this outbreak of S. sonnei resulted from poor sanitary procedures that probably allowed stool from a carrier to contaminate oysters either just before or after they were taken aboard the boat.