Pathogenic detection and molecular tracing of a bacillary dysentery outbreak by Shigella sonnei in Huainan city / 中华预防医学杂志

Objective: To understand the virulence gene and drug resistance profile of Shigella sonnei outbreak in Huainan city, and conduct pathogenic traceability analysis. Methods: Water samples and feces related to an infectious diarrhea outbreak in Huainan city in August 2020 were collected for multiple pathogen detection. Virulence gene, drug sensitivity, pulse-field gel electrophoresis and whole genome sequencing of Shigella isolates were analyzed respectively. Results: 38 strains of Shigella sonnei were detected in 56 samples of mucilage feces with a positive rate 67.86%, and all serotypes were Shigella sonnei Phase I. Three strains of Shigella sonnei were detected by fluorescence PCR in the Gram-negative (GN) bacterial enrichment solution of terminal water and well water. Virulence genes were ipaH positive (38), ipaH/ial (31) and ipaH/ial/sen positive (1), respectively. The drug resistance spectrum showed that 9 of 14 antibiotics were 100% resistant, and only imipenem, chloramphenicol, ceftazidime and ciprofloxacin were effective drugs. XbaⅠ restriction enzyme map type of 36 isolates was completely consistent, and the ST type analysis of 3 strains was ST152. Whole genome sequencing and analysis verified that the outbreak was caused by a single clonal group of strains, and revealed that the isolates of the outbreak were clustered into a large cluster with 3 Chinese strains and 1 Korean strain in the database, far away from the strains of other countries. Conclusion: The outbreak is caused by a single clone of Shigella sonnei, which are low virulence strains and have multiple drug resistance.

Effects of daily mean temperature and other meteorological variables on bacillary dysentery in Beijing-Tianjin-Hebei region, China

BACKGROUND@#Although previous studies have shown that meteorological factors such as temperature are related to the incidence of bacillary dysentery (BD), researches about the non-linear and interaction effect among meteorological variables remain limited. The objective of this study was to analyze the effects of temperature and other meteorological variables on BD in Beijing-Tianjin-Hebei region, which is a high-risk area for BD distribution.@*METHODS@#Our study was based on the daily-scale data of BD cases and meteorological variables from 2014 to 2019, using generalized additive model (GAM) to explore the relationship between meteorological variables and BD cases and distributed lag non-linear model (DLNM) to analyze the lag and cumulative effects. The interaction effects and stratified analysis were developed by the GAM.@*RESULTS@#A total of 147,001 cases were reported from 2014 to 2019. The relationship between temperature and BD was approximately liner above 0 °C, but the turning point of total temperature effect was 10 °C. Results of DLNM indicated that the effect of high temperature was significant on lag 5d and lag 6d, and the lag effect showed that each 5 °C rise caused a 3% [Relative risk (RR) = 1.03, 95% Confidence interval (CI): 1.02-1.05] increase in BD cases. The cumulative BD cases delayed by 7 days increased by 31% for each 5 °C rise in temperature above 10 °C (RR = 1.31, 95% CI: 1.30-1.33). The interaction effects and stratified analysis manifested that the incidence of BD was highest in hot and humid climates.@*CONCLUSIONS@#This study suggests that temperature can significantly affect the incidence of BD, and its effect can be enhanced by humidity and precipitation, which means that the hot and humid environment positively increases the incidence of BD.

Infestación de Musca domestica L. (Díptera, Muscidae) en faenadoras avícolas / Infestation of Musca domestica L. (Diptera, Muscidae) in poultry slaughterhouses

Musca domestica (Diptera, Muscidae) es la mosca más común en todo el mundo. Más de 100 patógenos pueden causar enfermedades en humanos y animales por este tipo de insectos. Estos patógenos incluyen: diarrea infantil, ántrax, cólera, oftalmía, disentería bacilar, fiebre tifoidea y tuberculosis. Además, las moscas domésticas transmiten muchos de los huevos de helmintos como Enterobius vermicularis, Strongyloides stercoralis, Trichuris trichiura, Toxocara canis, y especies de Dipylidium, Diphyllobothriam, Hymenolepis, Taenia y Trichomonas. También puede transmitir quistes de protozoos y trofozoítos como E. histolytica y Giardia lamblia. Se determinó el índice de infestación por Musca domestica L. (Díptera, Muscidae) en una faenadora avícola ubicada en el Perú. Para ello se evaluó no sólo el tratamiento aplicado: protocolo de cola entomológica (T1), monitoreo de insfectación de mosca (T2) o comincación de lámparas LED UV más tabla de pegamento adhesivo (T3), sino también las diferentes zonas de faenadora: zonas sucias de descarga y estabulación (ZDE), preparación (ZP), zonas adicionales de sacrificio sanitario (ZSS), preparación de residuos orgánicos (ZPRO), conservación de los residuos orgánicos (ZCRO) y de conservación de sangre (ZCS). Los resultados demoestraron que, independientemente de la zona de operación, el tratamiento más efectivo para determinar la infestación por la mosca doméstica fue el combinado de lámpara LED junto con tablas de pegamento (T3), seguido del tratamiento de protocolo de cola entomológica (T1) y el tratamiento por Monitoreo de infestación de moscas (T2) independientemente de los días de recolección. Es importante seguir las diferentes normativas a fin de controlar y eliminar la presencia de moscas (y de otros insectos voladores) para evitar la contaminación y, por ende, enfermedades(AU)

Musca domestica (Diptera, Muscidae) is the most common fly in the world. More than 100 pathogens can cause diseases in humans and animals by these types of insects. These pathogens include: infant diarrhea, anthrax, cholera, ophthalmia, bacillary dysentery, typhoid fever, and tuberculosis. In addition, houseflies transmit many of the eggs of helminths such as Enterobius vermicularis, Strongyloides stercoralis, Trichuris trichiura, Toxocara canis, and Dipylidium, Diphyllobothriam, Hymenolepis, Taenia, and Trichomonas species. It can also transmit cysts of protozoa and trophozoites such as E. histolytica and Giardia lamblia. The infestation index by Musca domestica L. (Diptera, Muscidae) was determined in a poultry slaughterhouse located in Peru. For this, not only the applied treatment was evaluated: entomological glue protocol (T1), fly infestation monitoring (T2) or combination of UV LED lamps plus adhesive glue table (T3), but also the different slaughter areas: unloading and holding areas (ZDE), preparation (ZP), additional stamping-out areas (ZSS), preparation of organic waste (ZPRO), conservation of organic waste (ZCRO) and blood conservation (ZCS). The results showed that, regardless of the area of operation, the most effective treatment to determine housefly infestation was the LED lamp combined with glue boards (T3), followed by the entomological glue protocol treatment (T1 ) and the treatment by Monitoring of fly infestation (T2) regardless of the days of collection. It is important to follow the different regulations in order to control and eliminate the presence of flies (and other flying insects) to avoid contamination and, therefore, diseases(AU)

Laboratory-based surveillance of Shigella spp. from human clinical cases in Colombia, 1997-2018 / Vigilancia por el laboratorio de Shigella spp. aislada de casos clínicos humanos en Colombia, 1997-2018

Abstract | Introduction: Shigellosis is endemic in low-and middle-income countries, causing approximately 125 million episodes of diarrhea and leading to approximately 160.000 deaths annually one-third of which is associated with children. Objective: To describe the characteristics and antimicrobial resistance profiles of Shigella species recovered in Colombia from 1997 to 2018. Materials and methods: We received isolates from laboratories in 29 Colombian departments. We serotyped with specific antiserum and determined antimicrobial resistance and minimal inhibitory concentrations for ten antibiotics with Kirby-Bauer tests following the Clinical and Laboratory Standards Institute recommendations. Results: We analyzed 5,251 isolates of Shigella spp., most of them obtained from stools (96.4%); 2,511 (47.8%) were from children under five years of age. The two most common species were S. sonnei (55.1%) and S. fbxneri (41.7%). The highest resistance rate was that of tetracycline (88.1%) followed by trimethoprim-sulfamethoxazole (79.3%) and ampicillin (65.5%); 50.8% of isolates were resistant to chloramphenicol, 43.6% to amoxicillin/clavulanic acid, and less than 1% to cefotaxime, ceftazidime, gentamicin, and ciprofloxacin. In S. sonnei, the most common resistance profile corresponded to trimethoprim-sulfamethoxazole (92%) whereas in S. fbxneri the most common antibiotic profiles were multidrug resistance. Conclusions. In Colombia, children under five years are affected by all Shigella species. These findings should guide funders and public health officials to make evidence-based decisions for protection and prevention measures. The antimicrobial resistance characteristics found in this study underline the importance of combating the dissemination of the most frequently isolated species, S. sonnei and S. ftexneri.

Resumen | Introducción. La shigelosis es endémica en los países de ingresos bajos y medios y ocasiona aproximadamente 125 millones de episodios de diarrea y 160.000 muertes al año, un tercio de los cuales se presenta en niños. Objetivo. Describir las características y los perfiles de resistencia antimicrobiana en aislamientos de Shigella spp. recuperados en Colombia entre 1997 y 2018. Materiales y métodos. Los aislamientos provenían de laboratorios en 29 departamentos de Colombia. La serotipificación se hizo con antisueros específicos de Shigella spp. y, la determinación de los perfiles de resistencia y la concentración inhibitoria mínima de diez antibióticos, por Kirby-Bauer. Resultados. Se estudiaron 5.251 aislamientos de Shigella spp. obtenidos de materia fecal (96,4 %); el 47,8 % de ellos correspondía a niños menores de cinco años. Las especies más frecuentes fueron S. sonnei (55,1 %) y S. ftexneri (41,7 %). Se presentó resistencia a tetraciclina (88,1 %), trimetoprim-sulfametoxasol (79,3 %), ampicilina (65,5 %), cloranfenicol (50,8 %) y amoxicilina-acido clavulánico (43,6 %). La resistencia no superó el 1 % contra cefotaxime, ceftazidima, gentamicina y ciprofloxacina. Para S. sonnei, el perfil de resistencia más frecuente correspondió a trimetoprim-sulfametoxasol, en contraste con S. ftexneri, cuyos perfiles fueron todos multirresistentes. Conclusiones. Los niños menores de cinco años se vieron afectados por todas las especies de Shigella spp., aspecto que los legisladores en salud pública deben considerar a la hora de tomar decisiones en torno a las medidas de prevención y protección frente a esta enfermedad. Las características de resistencia antimicrobiana de los aislamientos de Shigella spp. en Colombia ponen de manifiesto la importancia de combatir la diseminación de las dos especies más frecuentes en casos clínicos, S. sonnei y S. ftexneri.

De cómo se gestó el alcantarillado de Santiago de Chile / About how was gestated the sewerage in Santiago de Chile

Resumen Puede considerarse que la red de acequias, diseñada por el alarife Gamboa en 1541 junto con el plano de los solares de la recién fundada ciudad de Santiago, fue el esqueleto que al correr de los siglos llevaría a la construcción de un alcantarillado. Durante el período colonial estas acequias, destinadas a aportar agua a las chacras, servirían para llevarse los desechos, no sólo orgánicos, sino de todo tipo, generando abusos y litigios entre los vecinos, que se intentaba controlar con múltiples leyes y reglamentos. El agua para beber, extraída del río Mapocho, era nauseabunda y fuente de infecciones entéricas, siendo mejor -y más cara- la acarreada desde las quebradas cordilleranas, como la de Ramón. Con el advenimiento de la República en el siglo XIX nació la preocupación por tener una estructura sanitaria similar a la europea, culminando con la idea de tener una red de alcantarillado, cuya construcción se iniciaría recién en 1905, luego de una larga discusión de varios proyectos.

Abstract It is possible to estimate as the skeleton for the body of one future sewerage in Santiago (Chile) the web of irrigation ditches designed for the "alarife" (a primitive architect) Gamboa in 1541. Along the three centuries of the colonial period, the ditches not only distributed water for the familial cultures, but also got away from the houses all kind of residues, not only organic, being a fountain of conflicts and fights between the neighbors, that multiple laws and warnings could not ever resolve. The water for drink was taken from the dirty Mapocho River, full of enteric bacteria, with the consequences of Salmonella and Shigella infections, being better but more expensive the water from the ravines near the city, transported on mules or horses. With the arrival of the Republic in 1810, the idea of a sewerage for Santiago similar to the Europeans was growing, and after one discussion and another, and after one project and another, its building started on 1905.

Associations between floods and bacillary dysentery cases in main urban areas of Chongqing, China, 2005-2016: a retrospective study

BACKGROUND@#Understanding the association between floods and bacillary dysentery (BD) incidence is necessary for us to assess the health risk of extreme weather events. This study aims at exploring the association between floods and daily bacillary dysentery cases in main urban areas of Chongqing between 2005 and 2016 as well as evaluating the attributable risk from floods.@*METHODS@#The association between floods and daily bacillary dysentery cases was evaluated by using distributed lag non-linear model, controlling for meteorological factors, long-term trend, seasonality, and day of week. The fraction and number of bacillary dysentery cases attributable to floods was calculated. Subgroup analyses were conducted to explore the association across age, gender, and occupation.@*RESULTS@#After controlling the impact of temperature, precipitation, relative humidity, long-term trend, and seasonality, a significant lag effect of floods on bacillary dysentery cases was found at 0-day, 3-day, and 4-day lag, and the cumulative relative risk (CRR) over a 7-lag day period was 1.393 (95%CI 1.216-1.596). Male had higher risk than female. People under 5 years old and people aged 15-64 years old had significantly higher risk. Students, workers, and children had significantly higher risk. During the study period, based on 7-lag days, the attributable fraction of bacillary dysentery cases due to floods was 1.10% and the attributable number was 497 persons.@*CONCLUSIONS@#This study confirms that floods can increase the risk of bacillary dysentery incidence in main urban areas of Chongqing within an accurate time scale, the risk of bacillary dysentery caused by floods is still serious. The key population includes male, people under 5 years old, students, workers, and children. Considering the lag effect of floods on bacillary dysentery, the government and public health emergency departments should advance to the emergency health response in order to minimize the potential risk of floods on public.

Acute diarrhea with blood: diagnosis and drug treatment / Diarreia aguda com sangue: diagnóstico e tratamento medicamentoso

Abstract Objective To restate the epidemiological importance of Shigella in acute diarrhea with blood, providing an overview of the treatment and stressing the need for the correct indication of antibiotic therapy. Sources of Data A search was carried out in the Medline and Scopus databases, in addition to the World Health Organization scientific documents and guidelines, identifying review articles and original articles considered relevant to substantiate the narrative review. Synthesis of Data Different pathogens have been associated with acute diarrhea with blood; Shigella was the most frequently identified. The manifestations of shigellosis in healthy individuals are usually of moderate intensity and disappear within a few days. There may be progression to overt dysentery with blood and mucus, lower abdominal pain, and tenesmus. Conventional bacterial stool culture is the gold standard for the etiological diagnosis; however, new molecular tests have been developed to allow the physician to initiate targeted antibacterial treatment, addressing a major current concern caused by the increasing resistance of Shigella. Prevention strategies include breastfeeding, hygiene measures, health education, water treatment, and the potential use of vaccines. Conclusions Acute diarrhea is an important cause of mortality in children under 5 years and shigellosis is the leading cause of acute diarrhea with blood worldwide. The current concern is the increase in microbial resistance to the recommended antibiotics, which brings an additional difficulty to therapeutic management. Although no vaccine is yet available against Shigella, several candidates are undergoing clinical trials, and this may be the most cost-effective preventative measure in future.

Resumo Objetivo Reiterar a importância epidemiológica da Shigella na diarreia aguda com sangue, fornecer uma visão geral do tratamento e ressaltar a necessidade da correta indicação da antibioticoterapia. Fontes dos dados Realizada pesquisa nos bancos de dados Medline e Scopus, além de documentos científicos e diretrizes da Organização Mundial da Saúde, com a identificação de artigos de revisão e artigos originais considerados relevantes para fundamentar a revisão do tipo narrativa. Síntese dos dados Diferentes patógenos têm sido associados à diarreia aguda com sangue, a Shigella é o mais frequente. As manifestações da shigelose em indivíduos saudáveis são geralmente de intensidade moderada e desaparecem em poucos dias. Pode haver progressão para disenteria franca com sangue e muco, dor em abdome inferior e tenesmo. A coprocultura bacteriana convencional é o padrão-ouro para o diagnóstico etiológico, porém novos testes moleculares foram desenvolvidos, os quais permitem ao médico iniciar tratamento antibacteriano direcionado, sanar uma grande preocupação atual, devido à crescente resistência da Shigella. Estratégias de prevenção incluem aleitamento, medidas de higiene, educação em saúde, tratamento da água e o potencial uso de vacinas. Conclusões A diarreia aguda é uma importante causa de mortalidade em crianças com menos de cinco anos e a shigelose é a principal causa de diarreia aguda com sangue em todo o mundo. A preocupação atual é o aumento da resistência microbiana aos antibióticos preconizados, o que traz uma dificuldade adicional ao manejo terapêutico. Embora ainda não exista vacina disponível para Shigella, várias candidatas estão em fase de testes clínicos, podem futuramente ser a medida preventiva mais custo-efetiva.

Reverse vaccinology approach for the identification and characterization of outer membrane proteins of Shigella flexneri as potential cellular- and antibody-dependent vaccine candidates

Dysentery by CTX-M Type ESBL Producing Shigella flexneri / Disentería por Shigella flexneri productora de BLEE tipo CTX-M

According to the World Health Organization, diarrheal infections cause 525 000 deaths of children under five years of age every year, and shigellosis. Shigellosis is a relevant cause of dysentery, which increases the morbidity and mortality in pediatric patients. Therefore, emergingthe emergence of antimicrobial resistant strains of Shigella is a concerningworrisome problem worldwide. We report the case of a 7-year-old patient with acute dysentery caused by CTX-M Type ESBL Producing Shigella flexneri, being. This was the first case treated in the Specialties Hospital of Specialties of the Armed Forces N°1, in Quito, Ecuador. The antibiogram demonstrated sensibilityshowed sensitivity to ampicillin-sulbactam. As a result, after five days of microbiologically directed treatment, the patient improved his condition without relapse. Proper clinical diagnoses and accurate laboratory studies like stool culture and antibiogram are crucial to givingindicate an appropriate therapy in infections caused by Shigella and other enteric bacilli(AU)

Según la Organización Mundial de la Salud, las infecciones diarreicas provocan 525 000 muertes de niños menores de cinco años de edad cada año. La shigelosis es una causa importante de disentería que aumenta la morbilidad y mortalidad de los pacientes pediátricos. Es por eso que el surgimiento de cepas de Shigella resistentes a los antibióticos es un preocupante problema a nivel mundial. Presentamos el caso de un paciente de 7 años de edad con disentería aguda provocada por Shigella flexneri productora de BLEE tipo CTX-M. Se trata del primer caso tratado en el Hospital de Especialidades de las Fuerzas Armadas Nº 1, en Quito, Ecuador. El antibiograma mostró sensibilidad a la combinación ampicilina/sulbactam. Al cabo de cinco días de tratamiento microbiológico, el paciente mejoró su estado y no se produjeron recaídas. Un diagnóstico clínico correcto, así como estudios precisos de laboratorio como los cultivos de heces y los antibiogramas, son vitales para indicar una terapia apropiada en las infecciones causadas por Shigella y otros bacilos entéricos(AU)

Enterobacterial repetitive intergenic consensus (ERIC)-PCR analysis as a reliable evidence for suspected Shigella spp. outbreaks

Abstract Background Shigellosis remains a serious public health problem and an important cause of morbidity and mortality worldwide. The aim of this study was to characterize fliC and the genetic relatedness of Shigella spp. isolated during a one-year period from children in a suspected outbreak in Tehran, Iran. Methods and results Fifty Shigella spp. were isolated from 3779 stool samples of children with diarrhea (prevalence rate: 1.32%). Among the isolates, 92% were characterized as Shigella sonnei, while 6% and 2% were identified as S. flexneri and S. boydii, respectively. S. dysenteriae was not recovered from the patients. All isolates were negative for fliC except for Shigella standard strains. The enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) profiles allowed differentiating the 50 isolates into 5 ERIC types, which were grouped into five clusters (ET1-ET5). Computer-assisted clustering of the strains showed a high degree of similarity among the isolates. Conclusion In conclusion, given the clonal correlation of the Shigella strains isolated in this study and the lack of fliC among them, we propose that probably a single or limited fliC-defected Shigella clone spread and caused the outbreak.

Bacteriemia por Shigella flexneri en dos lactantes / Shigella flexneri bacteremia in children: two case report and review of literature

Resumen Shigella spp. es el aislamiento microbiológico más frecuente en las diarreas bacterianas en Argentina. Clínicamente puede causar desde una diarrea acuosa hasta disentería. En forma infrecuente causa complicaciones extraintestinales, con una incidencia de bacteriemia desde 0,4 a 7,3%; asociado a factores de riesgo como niños menores de un año de edad e inmunodeficiencias, entre otros. Presentamos los casos clínicos de dos lactantes con bacteriemia por Shigella flexneri, que consultaron por fiebre y diarrea, uno de ellos con diagnóstico de inmunodeficiencia primaria.

Shigella spp. is the most frequent micro-biological isolation in bacterial diarrhea in Argentina. It causes a watery diarrhea or dysenteric disease. It rarely causes extraintestinal problems. It has an incidence of bacteremia of 0,4-7,3%, and its appearance compels us to look for associated risk factors, as children under one year of age and immunodeficiency, among others. We describe two children with Shigella flexneri bacteremia. They presented with fever and diarrhea. One of them had primary immune deficiency.

Genotypic Diversity of Multidrug Resistant Shigella species from Iran

BACKGROUND: In many developing countries, shigellosis is endemic and also occurs in epidemics and treatment of multidrug-resistant (MDR) isolates are important. The aims of this study were to determine the antimicrobial susceptibility, prevalence of class 1 and 2 integrons and the clonal relatedness of isolates. MATERIALS AND METHODS: Antimicrobial susceptibility tests were performed by disc diffusion method. Polymerase chain reaction (PCR)-sequencing technique was employed for detection and characterization of integrons. The genetic relatedness was evaluated by using enterobacterial repetitive intergenic consensus (ERIC) PCR. RESULTS: There was a high percentage of resistance to trimethoprim-sulfamethoxazole (TMP/SMX) (93.7%), ampicillin (AMP) (87.3%), streptomycin (STR) (84.5%) and tetracycline (TET) (78.9%). Multidrug resistant phenotype was seen in 95.1% of total isolates. Most common MDR profile was TMP/SMX/STR/AMP resistant pattern. Among the 142 Shigella spp. analyzed in this study, 28 isolates were positive for class 1 integron with two types of gene cassette arrays (dfrA17/aadA5 = 31.7% and dfrA7 = 3.8%). The class 2 integron was more frequently detected among the isolates (94.7%) with dfrA1/sat1/aadA1 (69.4%) and dfrA1/sat1 (30.6%) gene cassettes. ERIC-PCR results showed 6, 5, 4 and 3 main genotypes among S. flexneri, S. sonnei, S. boydii and S. dysenteriae isolates, respectively. CONCLUSIONS: Our findings revealed that multidrug resistant Shigella species with high prevalence of class 2 integron were very common in Iran. In addition, ERIC-PCR patterns showed limited variety of clones are responsible for shigellosis in the region of the study.

Genotypic Diversity of Multidrug Resistant Shigella species from Iran

BACKGROUND: In many developing countries, shigellosis is endemic and also occurs in epidemics and treatment of multidrug-resistant (MDR) isolates are important. The aims of this study were to determine the antimicrobial susceptibility, prevalence of class 1 and 2 integrons and the clonal relatedness of isolates. MATERIALS AND METHODS: Antimicrobial susceptibility tests were performed by disc diffusion method. Polymerase chain reaction (PCR)-sequencing technique was employed for detection and characterization of integrons. The genetic relatedness was evaluated by using enterobacterial repetitive intergenic consensus (ERIC) PCR. RESULTS: There was a high percentage of resistance to trimethoprim-sulfamethoxazole (TMP/SMX) (93.7%), ampicillin (AMP) (87.3%), streptomycin (STR) (84.5%) and tetracycline (TET) (78.9%). Multidrug resistant phenotype was seen in 95.1% of total isolates. Most common MDR profile was TMP/SMX/STR/AMP resistant pattern. Among the 142 Shigella spp. analyzed in this study, 28 isolates were positive for class 1 integron with two types of gene cassette arrays (dfrA17/aadA5 = 31.7% and dfrA7 = 3.8%). The class 2 integron was more frequently detected among the isolates (94.7%) with dfrA1/sat1/aadA1 (69.4%) and dfrA1/sat1 (30.6%) gene cassettes. ERIC-PCR results showed 6, 5, 4 and 3 main genotypes among S. flexneri, S. sonnei, S. boydii and S. dysenteriae isolates, respectively. CONCLUSIONS: Our findings revealed that multidrug resistant Shigella species with high prevalence of class 2 integron were very common in Iran. In addition, ERIC-PCR patterns showed limited variety of clones are responsible for shigellosis in the region of the study.

Distributed lag effects on the relationship between daily mean temperature and the incidence of bacillary dysentery in Lanzhou city / 北京大学学报(医学版)

OBJECTIVE@#To discuss the lag effects of daily average temperature on the daily cases of bacillary dysentery in Lanzhou city.@*METHODS@#The data of daily cases of bacillary dysentery were collected during 2008 and 2015 in the city, and the meteorological data at the same period was integrated. The distributed lag non-linear model was used to analyze the relevance between daily average temperature and the daily cases of bacillary dysentery.@*RESULTS@#The exposure response relationship between the daily temperature and the incidence of bacillary dysentery was "J" type, the lowest incidence temperature was 17 °C, and the effect of high temperature on different gender and age groups was higher than that of the intermediate effect. The effect of high temperature and intermediate effect on the male and female groups showed an acute effect, the effect of the day was the highest, followed by fluctuations in temperature, and the greater the impact on women. In different age groups, high temperature effect and the intermediate effect of bacterial dysentery in 0-3 years old groups were the biggest; the effects of high and intermediate temperature on people aged 0-3 and 19-64 year all showed acute effects, which were the maximum value at the day, then decreased volatility; and for people aged over 65 years, the day after the onset, decreases and then increases slowly. There were obviously increasing risks of bacillary dysentery both the high temperature (32 °C) and the middle temperature (26 °C) with respect to 17 °C. The accumulative effects were highest at lag14 days, and the RR (95%CI) values of middle temperature was 2.30 (1.53-3.13), 2.45 (1.65-3.30), 2.41 (1.59-3.28), 2.54 (1.40-3.79), 1.82 (0.41-3.43), 1.98 (1.11-2.93), and 1.73 (0.68-2.88) among the males, females, 0-3 years old, 4-11 years old, 12-18 years old, 19-64 years old and over 65 years old people, respectively; while the high temperature was 2.93 (1.38-4.69), 3.08 (1.48- 4.90), 3.26 (1.60-5.16), 3.12 (1.06-5.56), 1.94 (0.73-5.39), 2.31 (0.54-4.36), and 2.06 (0.02-4.51), respectively.@*CONCLUSION@#The high temperature may increase risks of bacillary dysentery, and the females and younger people were the sensitive population. Meteorological factors play an important role in the occurrence and development of bacillary dysentery in Lanzhou. The incidence of bacillary dysentery is affected by multiple meteorological factors, but the primary one is high temperature. The temperature has not a direct effect on the incidence of bacillary dysentery, but an indirect influence in different populations through the impacts of various aspects of the incidence of bacterial dysentery (residents living habits, communication channels and the habits of the susceptible population).

Shigella sp: um problema de saúde pública / Shigella sp: a public health problem

O aumento do consumo de refeições fora de casa está associado ao aumento das Doenças Veiculadas por Alimentos (DVA), que são provenientes do consumo de alimentos e água contaminados, principalmente, devido à falta de higiene no preparo dos alimentos e à ausência, em muitos casos, do tratamento da água usada no preparo destes alimentos. A shigelose é uma DVA que se caracteriza como uma doença inflamatória do trato gastrointestinal causada pela Shigella cujos sintomas e características se assemelham à salmonelose. O gênero Shigella possui quatro espécies: S. dysenteriae, S. flexneri, S. boydii e S. sonnei. Para a realização deste trabalho foi realizado levantamento de artigos publicados em revistas científicas sobre o tema, com o objetivo de verificar a incidência de Shigella em alimentos abordando suas características e danos provocados à saúde.(AU)

Profiling of Virulence-associated Factors in Shigella Species Isolated from Acute Pediatric Diarrheal Samples in Tehran, Iran

OBJECTIVES: The genus Shigella comprises the most infectious and diarrheagenic bacteria causing severe diseases, mostly in children under five years of age. This study aimed to detect nine virulence genes (ipaBCD, VirA, sen, set1A, set1B, ial, ipaH, stx, and sat) in Shigella species (spp.) using multiplex polymerase chain reaction (MPCR) and to determine the relation of Shigella spp. from pediatric diarrheal samples with hospitalization and bloody diarrhea in Tehran, Iran. METHODS: Shigella spp. were isolated and identified using standard microbiological and serological methods. The virulence genes were detected using MPCR. RESULTS: Seventy-five Shigella spp. (40 S. sonnei, 33 S. flexneri, 1 S. dysenteriae, and 1 S. boydii) were isolated in this study. The prevalence of ial, sen, sat, set1A, and set1B was 74.7%, 45.4%, 28%, 24%, and 24%, respectively. All S. flexneri isolates, while no S. sonnei, S. dysenteriae, or S. boydii isolates, contained sat, set1A, and set1B. All isolates were positive for ipaH, ipaBCD, and virA, while one (1.4%) of the isolates contained stx. The highest prevalence of virulence determinants was found in S. flexneri serotype IIa. Nineteen (57.6%) of 33 S. flexneri isolates were positive for ipaBCD, ipaH, virA, ial, and sat. The sen determinants were found to be statistically significantly associated with hospitalization and bloody diarrhea (p = 0.001). CONCLUSION: This study revealed a high prevalence of enterotoxin genes in S. flexneri, especially in serotype 2a, and has presented relations between a few clinical features of shigellosis and numerous virulence determinants of clinical isolates of Shigella spp.

Characterization of Extended-Spectrum β-Lactamase Genes of Shigella flexneri Isolates With Fosfomycin Resistance From Patients in China

BACKGROUND: The emergence of fosfomycin resistance and extended-spectrum β-lactamase (ESBL) genes is a serious threat to public health and a new challenge in shigellosis treatment. The purpose of this study was to identify fosfomycin resistance and characterize β-lactamase genes in fos-carrying isolates of Shigella flexneri from patients in China. METHODS: A total of 263 S. flexneri isolates were collected from 34 hospitals in the Anhui Province of China during September 2012-September 2015 and screened for fosA3, fosA, and fosC2 by PCR amplification and sequencing. The fos-carrying isolates were then screened for β-lactamase genes. The clonal relationships between fosA3-carrying isolates, the transmissibility of fosfomycin resistance, replicon types of plasmids carrying fosfomycin resistance genes and other associated resistance genes were investigated. RESULTS: Twenty-five of the 263 isolates (9.5%) showed resistance to fosfomycin, and 18 (6.8%) were positive for fosA3. None of the isolates was positive for fosA or fosC2. Seventeen of the isolates carrying fosA3 (94%) were CTX-M producers (seven CTX-M-55, five CTX-M-14, and five CTX-M-123), while three (16.7%) were TEM producers (TEM-1).Sixteen (88.9%) fosA3-carrying isolates exhibited multi-drug resistance. The replicon types of the 13 fosA3-carrying plasmids were IncF (n=13), IncHI2 (n=3), IncIl-Ir (n=2), and IncN (n=1). CONCLUSIONS: Our results indicated that fosA3 could spread through plasmids in S. flexneri isolates, along with the bla(CTX-M) and bla(TEM), which facilitate its quick dispersal. To the best of our knowledge, this is the first report of CTX-M-123-type ESBLs in S. flexneri isolates from patients in China.

The importance of integrons for development and propagation of resistance in Shigella: the case of Latin America

Abstract In Latin America, the disease burden of shigellosis is found to coexist with the rapid and rampant spread of resistance to commonly used antibiotics. The molecular basis of antibiotic resistance lies within genetic elements such as plasmids, transposons, integrons, genomic islands, etc., which are found in the bacterial genome. Integrons are known to acquire, exchange, and express genes within gene cassettes and it is hypothesized that they play a significant role in the transmission of multidrug resistance genes in several Gram-negative bacteria including Shigella. A few studies have described antibiotic resistance genes and integrons among multidrug resistant Shigella isolates found in Latin America. For example, in Brazil, Bolivia, Chile, Costa Rica and Peru, class 1 and class 2 integrons have been detected among multidrug resistant strains of Shigella; this phenomenon is more frequently observed in S. flexneri isolates that are resistant to trimethoprim, sulfamethoxazole, streptomycin, ampicillin, chloramphenicol, and tetracycline. The gene cassette sul2, which is frequently detected in Shigella strains resistant to the sulfonamides, suggests that the sulfonamide-resistant phenotype can be explained by the presence of the sul2 genes independent of the integron class detected. It is to be noted that sul3 was negative in all isolates analyzed in these studies.The high frequency of sulfonamide (as encoded by sul2) and trimethoprim resistance is likely to be a result of the recurrent use of trimethoprim sulfamethoxazole as a popular regimen for the treatment of shigellosis. The observed resistance profiles of Shigella strains confirm that ampicillin and trimethoprim-sulfamethoxazole are ineffective as therapeutic options. In-depth information regarding antibiotic resistance mechanism in this pathogen is needed in order to develop suitable intervention strategies. There is a pressing need for regional and local antimicrobial resistance profiling of Shigella to be included as a part of the public health strategy.

Long-term Clinical Course of Post-infectious Irritable Bowel Syndrome After Shigellosis: A 10-year Follow-up Study

BACKGROUND/AIMS: A limited number of studies are available regarding the long-term natural history of post-infectious irritable bowel syndrome (PI-IBS). We aimed to investigate the long-term clinical course of PI-IBS. METHODS: A prospective cohort study was conducted from a 2001 shigellosis outbreak in a Korean hospital with about 2000 employees. A cohort of 124 hospital employees who were infected by Shigella sonnei due to contaminated food in the cafeteria, and 105 sex- and age-matched, non-infected, controls were serially followed for their bowel symptoms by questionnaire surveys for 10 years. RESULTS: The Shigella-infected cohort showed significantly higher odds ratio for irritable bowel syndrome (IBS) at 1-year (11.90; 95% CI, 1.49-95.58) and 3-year (3.93; 95% CI, 1.20-12.86) follow-up, compared to their controls. However, corresponding odds ratio for PI-IBS was not significantly increased at 5-year (1.88; 95% CI, 0.64-5.54) and 8-year (1.87; 95% CI, 0.62-5.19) follow-up. At 10-year follow-up survey, the prevalence of IBS was similar for the Shigella-infected cohort and their controls (23.3% versus 19.7%, P = 0.703). Risk factors which were independently associated with PI-IBS among the Shigella-infected cohort included younger age, previous history of functional bowel disorder, and longer duration of diarrhea at baseline. CONCLUSIONS: Patients who were infected by Shigella sonnei experienced significantly increased risk of IBS until 3 years after shigellosis, and modestly increased risk until 8 years, but showed similar risk of IBS with uninfected controls at 10 years post-infection. PI-IBS is quite a chronic disorder, and follows a long-term natural course.

Shigellosis: A truly neglected disease in Papua New Guinea

@#Diarrhoeal diseases still affect many people, especially children living in impoverished and under-developed settings. In Papua New Guinea (PNG) diarrhoea remains one of the leading causes of hospitalization and a major cause of death. Here, we focus on the role of Shigella in diarrhoeal illness in PNG, and provide an overview of the causative organism and the illness. A review of the available data on the aetiology of diarrhoea in PNG suggests that shigellosis is a major cause of diarrhoeal illness. Since shigellosis can cause protracted and life-threatening illness an appreciation of the burden of shigellosis is important to aid in the development of optimal prevention and control strategies. Treatment strategies for all cases of moderate-severe diarrhoeal illness should centre on rehydration, but where antimicrobial treatment is required consideration should be given to the increasing antimicrobial resistance observed in Shigella isolates in PNG.