The Enterics for Global Health (EFGH) Shigella Surveillance Study in Peru.

Background: The Enterics for Global Health (EFGH) Peru site will enroll subjects in a periurban area of the low Amazon rainforest. The political department of Loreto lags behind most of Peru in access to improved sources of water and sanitation, per capita income, children born <2.5 kg, and infant and child mortality. Chronic undernutrition as manifested by linear growth shortfalls is common, but wasting and acute malnutrition are not. Methods: The recruitment of children seeking care for acute diarrheal disease takes place at a geographic cluster of government-based primary care centers in an area where most residents are beneficiaries of free primary healthcare. Results: Rates of diarrheal disease, dysentery, and Shigella are known to be high in the region, with some of the highest rates of disease documented in the literature and little evidence in improvement over the last 2 decades. This study will update estimates of shigellosis by measuring the prevalence of Shigella by polymerase chain reaction and culture in children seeking care and deriving population-based estimates by measuring healthcare seeking at the community level. Conclusions: Immunization has been offered universally against rotavirus in the region since 2009, and in a context where adequate water and sanitation are unlikely to obtain high standards in the near future, control of principal enteropathogens through immunization may be the most feasible way to decrease the high burden of disease in the area in the near future.

Molecular characterization of virulence and antimicrobial resistance profile of Shigella species isolated from children with moderate to severe diarrhea in northeastern Brazil.

Molecular characterization of virulence and antimicrobial resistance profiles were determined for Shigella species isolated from children with diarrhea in Fortaleza, Brazil. Fecal specimens were collected along with socioeconomic and clinical data from children with moderate to severe diarrhea requiring emergency care. Shigella spp. were isolated by standard microbiological techniques, and we developed 4 multiplex polymerase chain reaction assays to detect 16 virulence-related genes (VRGs). Antimicrobial susceptibility tests were performed using disk diffusion assays. S. flexneri and S. sonnei were the predominant serogroups. S. flexneri was associated with low monthly incomes; more severe disease; higher number of VRGs; and presence of pic, set, and sepA genes. The SepA gene was associated with more intense abdominal pain. S. flexneri was correlated with resistance to ampicillin and chloramphenicol, whereas S. sonnei was associated with resistance to azithromycin. Strains harboring higher numbers of VRGs were associated with resistance to more antimicrobials. We highlight the correlation between presence of S. flexneri and sepA, and increased virulence and suggest a link to socioeconomic change in northeastern Brazil. Additionally, antimicrobial resistance was associated with serogroup specificity in Shigella spp. and increased bacterial VRGs.

Virulence factors and mechanisms of antimicrobial resistance in Shigella strains from periurban areas of Lima (Peru).

The study was aimed to describe the serotype, mechanisms of antimicrobial resistance, and virulence determinants in Shigella spp. isolated from Peruvian children. Eighty three Shigella spp. were serogrouped and serotyped being established the antibiotic susceptibility. The presence of 12 virulence factors (VF) and integrase 1 and 2, along with commonly found antibiotic resistance genes was established by PCR. S. flexneri was the most relevant serogroup (55 isolates, 66%), with serotype 2a most frequently detected (27 of 55, 49%), followed by S. boydii and S. sonnei at 12 isolates each (14%) and S. dysenteriae (four isolates, 5%). Fifty isolates (60%) were multi-drug resistant (MDR) including 100% of S. sonnei and 64% of S. flexneri. Resistance levels were high to trimethoprim-sulfamethoxazole (86%), tetracycline (74%), ampicillin (67%), and chloramphenicol (65%). Six isolates showed decreased azithromycin susceptibility. No isolate was resistant to nalidixic acid, ciprofloxacin, nitrofurantoin, or ceftriaxone. The most frequent resistance genes were sul2 (95%), tet(B) (92%), cat (80%), dfrA1 (47%), blaOXA-1like (40%), with intl1 and intl2 detected in 51 and 52% of the isolates, respectively. Thirty-one different VF profiles were observed, being the ipaH (100%), sen (77%), virA and icsA (75%) genes the most frequently found. Differences in the prevalence of VF were observed between species with S. flexneri isolates, particularly serotype 2a, possessing high numbers of VF. In conclusion, this study highlights the high heterogeneity of Shigella VF and resistance genes, and prevalence of MDR organisms within this geographic region.

Patrones de susceptibilidad antimicrobiana de cepas de Shigella sonnei aisladas durante tres períodos diferentes en la Región Metropolitana, Chile / Antibiotic susceptibility patterns among Shigella sonnei, isolated during three different periods in Región Metropolitana, Chile

Background: Shigella sonnei gastroenteritis improves clinically and microbiologically with antibacterial treatment; however choosing a useful drug is a universal challenge because of in vitro susceptibility of S. sonnei frequently evolves to be resistant. Objective: To evaluate in vitro susceptibility of S. sonnei strains isolated from patients attending at the Chilean Región Metropolitana and to know the evolution that resistant patterns of S. sonnei have experienced. Material: In this study, the antimicrobial susceptibility profile of 277 isolates of Shigella sonnei was compared. The analyzed periods of time were: period I (1995-1997) 85 strains; period II (2004-2006) 92 strains and period III (2008-2009) 100 strains, in Santiago, Chile. The method performed to analyze susceptibility patterns was the disc diffusion (Kirby-Bauer). Results: The strains showed rates of resistance to ampicillin: period I, 85.8%; period II, 53.3%; period III, 100%, trimethoprim/sulfamethoxazole: period I, 50.5%; period, II 46.7%; period III, 100%, chloramphenicol: period I, 36.4%; period II, 12%; period III, 100% and tetracycline: period I, 38.8%; period II, 30.4%; period III, 100%. 98.9% of the strains showed susceptibility to quinolones. Significant differences were observed in patterns of antimicrobial resistance for both individuals and for multidrug resistance (≥ 3 antimicrobials) in the three periods (p < 0.001, χ2 test). Of all resistant strains, 17% were resistant to 1 or 2 antibiotics, while 65.7% showed a pattern of multidrug resistance; 100% of the period III strains presented multidrug resistance. Conclusion: These results showed the temporal resistance dynamics of S. sonnei circulating strains in the Chilean Región Metropolitana. Due to the endemic behavior of shigellosis in Chile, it is urgent to maintain permanent surveillance of antimicrobial resistance profiles to improve both prevention and treatment of shigellosis.

Introducción: La infección entérica producida por Shigella sonnei mejora clínicamente y microbiológicamente con antibioterapia; sin embargo, la elección del antimicrobiano es un problema universal pues la susceptibilidad in vitro de S. sonnei evoluciona frecuentemente hacia la resistencia. Objetivo: Evaluar la susceptibilidad in vitro a antimicrobianos de S. sonnei y conocer la evolución que han experimentado los patrones de resistencia de cepas aisladas de cuadros clínicos en pacientes de la Región Metropolitana, Chile. Material y Métodos: Se comparó el perfil de susceptibilidad a antimicrobianos, de 277 cepas clínicas de S. sonnei aisladas durante tres períodos: período I (1995-1997) 85 cepas; período II (2004-2006) 92 cepas y período III (2008-2009) 100 cepas, en Santiago, Chile. El perfil de susceptibilidad a antimicrobianos se determinó mediante test de difusión en agar. Resultados: Las tasas de resistencia de las cepas en los periodos I, II y III respectivamente fueron: ampicilina: 85,8%; 53,3%; 100%, cotrimoxazol: 50,5%; 46,7%; 100%, cloranfenicol: 36,4%; 12%; 100% y tetraciclina: 38,8%; 30,4%; 100%. El 98,9% de las cepas fue susceptible a quinolonas. Se observó diferencias significativas en los porcentajes de resistencia para antimicrobianos individuales y multi-resistencia (≥ 3 antimicrobianos) en los tres períodos (p < 0,001; Test de χ2). De las cepas resistentes, 17% presentó resistencia a uno ó dos antimicrobianos, 65,7% mostró multi-resistencia antimicrobiana. El 100% de las cepas del período III presentó multi-resistencia. Discusión: Estos resultados evidencian la dinámica temporal de la resistencia en cepas de S. sonnei circulantes en la Región Metropolitana. Dado que en Chile la shigelosis tiene un carácter endémico, es prioritario mantener una vigilancia constante de los perfiles de resistencia a antimicrobianos, para mejorar la prevención y el tratamiento de la shigelosis.

Antimicrobial resistance and PCR-ribotyping of Shigella responsible for foodborne outbreaks occurred in southern Brazil

Little information about Shigella responsible for foodborne shigellosis is available in Brazil. The present study aimed to investigate the antimicrobial resistance and PCR-ribotyping patterns of Shigella isolates responsible for foodborne outbreaks occurred in Rio Grande do Sul State (RS), Southern Brazil in the period between 2003 and 2007. Shigella strains (n=152) were isolated from foods and fecal samples of victims of shigellosis outbreaks investigated by the Surveillance Service. Identification of the strains at specie level indicated that 71.1 percent of them were S. flexneri, 21.5 percent S. sonnei, and 0.7 percent S. dysenteriae. Ten strains (6.7 percent) were identified only as Shigella spp. An increasing occurrence of S. sonnei was observed after 2004. Most of the strains were resistant to streptomycin (88.6 percent), followed by ampicillin (84.6 percent), and sulfamethoxazole/trimethoprim (80.5 percent). Resistant strains belonged to 73 patterns, and pattern A (resistance to ampicillin, sulfamethoxazole/trimethoprim, tetracycline, streptomycin, chloramphenicol, and intermediate resistance to kanamycin) grouped the largest number of isolates (n=36). PCR-ribotyping identified three banding patterns (SH1, SH2, and SH3). SH1 grouped all S. flexneri and SH2 grouped all S. sonnei. The S. dysenteriae strain belonged to group SH3. According to the results, several Shigella isolates shared the same PCR-rybotyping banding pattern and the same resistance profile, suggesting that closely related strains were responsible for the outbreaks. However, other molecular typing methods need to be applied to confirm the clonal relationship of these isolates.

Conocimientos sobre shigellosis y su manejo epidemiológico en personal médico / Knowledges on shigellosis and its epidemiological management in medical staff

Introducción: la Shigella como agente causal de episodios diarreicos con sangre ha sido el germen aislado con mayor frecuencia en los laboratorios clínicos, no obstante, el número de casos reportados por el Sistema de Enfermedades de Declaración Obligatoria es inferior, lo que demuestra un subregistro en su notificación. Objetivos: elevar el nivel de conocimientos de médicos y alumnos internos sobre la shigellosis. Métodos: se realizó un estudio cuasi experimental antes-después, de una intervención educativa sobre la shigellosis y su manejo epidemiológico. La investigación se hizo en los policlínicos comunitarios docentes Marcio Manduley y Nguyen Van Troi en el período de enero a junio de 2008. La muestra quedó conformada por 64 médicos, de ellos 21 eran alumnos internos. Todos expresaron su consentimiento para participar en la investigación. Se aplicó la prueba no paramétrica ji cuadrada con un nivel de significación de p < 0,05. Los datos se expresaron en valores absolutos y relativos. Resultados: antes de la intervención se observó que los conocimientos taxonómicos eran buenos en solo 9 encuestados para el 14,06 por ciento, después de la intervención, el número de personas con buen nivel de conocimientos ascendió hasta el 90,63 por ciento. Se constató que el personal médico tenía escaso nivel de conocimientos sobre los principales síntomas de inicio de la shigellosis. Los encuestados con buenos conocimientos sobre las principales medidas profilácticas para prevenir la enfermedad, aumentaron significativamente después de la intervención e igual comportamiento se observó en relación con el tratamiento idóneo en pacientes con Shigella. Conclusiones: la intervención educativa elevó el nivel de conocimientos en el personal médico sobre Shigella. Es necesario continuar promoviendo e investigando esta temática en el nivel primario de atención y extender un plan de acción no sólo a los hospitales, policlínicos y consultorios sino que ...(AU)

Introduction: Shigella as causal agent of diarrheic episodes with presence of blood has been the more frequent isolated agent in clinical laboratories; however, the number of cases reported by System of Diseases of Mandatory Statement is lower demonstrating a sub-registry of its notification. Objectives: to confirm the knowledge level of medical staff on the Shigellosis. Methods: a quasi-experimental study was conducted before and after a educational intervention on the Shigellosis and its epidemiological management. Research was made in the "Marcio Manduley" and "Nguyen Van Troi" Teaching and Community polyclinics from January to June, 2008. Sample included 43 physicians and 21 internal students in which the intervention was applied. Information was obtained by application of anonymous questionnaire. Results: before intervention it was possible to verify that taxonomic knowledges were satisfactory in only 9 polled persons for a 14,06 percent, after it, the figure of persons with a good level of knowledges raised to 90,63 percent. Authors confirmed that the medical staff had limited knowledges on the main symptoms of Shigellosis onset. The persons polled with high knowledges on main prophylactic measures to prevent this disease, increase significantly after intervention and a similar behavior was noted in relation to subject on suitable treatment in Shigella patients. Conclusions: educational intervention raised the knowledge level on Shigella in the medical staff. It is necessary to continue promoting and researching this subject matter at primary care level and to extend an action plan not only to hospitals, polyclinics and consulting rooms but also to involve family..(AU)

Conocimientos sobre shigellosis y su manejo epidemiológico en personal médico / Knowledges on shigellosis and its epidemiological management in medical staff

Introducción: la Shigella como agente causal de episodios diarreicos con sangre ha sido el germen aislado con mayor frecuencia en los laboratorios clínicos, no obstante, el número de casos reportados por el Sistema de Enfermedades de Declaración Obligatoria es inferior, lo que demuestra un subregistro en su notificación. Objetivos: elevar el nivel de conocimientos de médicos y alumnos internos sobre la shigellosis. Métodos: se realizó un estudio cuasi experimental antes-después, de una intervención educativa sobre la shigellosis y su manejo epidemiológico. La investigación se hizo en los policlínicos comunitarios docentes Marcio Manduley y Nguyen Van Troi en el período de enero a junio de 2008. La muestra quedó conformada por 64 médicos, de ellos 21 eran alumnos internos. Todos expresaron su consentimiento para participar en la investigación. Se aplicó la prueba no paramétrica ji cuadrada con un nivel de significación de p < 0,05. Los datos se expresaron en valores absolutos y relativos. Resultados: antes de la intervención se observó que los conocimientos taxonómicos eran buenos en solo 9 encuestados para el 14,06 por ciento, después de la intervención, el número de personas con buen nivel de conocimientos ascendió hasta el 90,63 por ciento. Se constató que el personal médico tenía escaso nivel de conocimientos sobre los principales síntomas de inicio de la shigellosis. Los encuestados con buenos conocimientos sobre las principales medidas profilácticas para prevenir la enfermedad, aumentaron significativamente después de la intervención e igual comportamiento se observó en relación con el tratamiento idóneo en pacientes con Shigella. Conclusiones: la intervención educativa elevó el nivel de conocimientos en el personal médico sobre Shigella. Es necesario continuar promoviendo e investigando esta temática en el nivel primario de atención y extender un plan de acción no sólo a los hospitales, policlínicos y consultorios sino que...

Introduction: Shigella as causal agent of diarrheic episodes with presence of blood has been the more frequent isolated agent in clinical laboratories; however, the number of cases reported by System of Diseases of Mandatory Statement is lower demonstrating a sub-registry of its notification. Objectives: to confirm the knowledge level of medical staff on the Shigellosis. Methods: a quasi-experimental study was conducted before and after a educational intervention on the Shigellosis and its epidemiological management. Research was made in the "Marcio Manduley" and "Nguyen Van Troi" Teaching and Community polyclinics from January to June, 2008. Sample included 43 physicians and 21 internal students in which the intervention was applied. Information was obtained by application of anonymous questionnaire. Results: before intervention it was possible to verify that taxonomic knowledges were satisfactory in only 9 polled persons for a 14,06 percent, after it, the figure of persons with a good level of knowledges raised to 90,63 percent. Authors confirmed that the medical staff had limited knowledges on the main symptoms of Shigellosis onset. The persons polled with high knowledges on main prophylactic measures to prevent this disease, increase significantly after intervention and a similar behavior was noted in relation to subject on suitable treatment in Shigella patients. Conclusions: educational intervention raised the knowledge level on Shigella in the medical staff. It is necessary to continue promoting and researching this subject matter at primary care level and to extend an action plan not only to hospitals, polyclinics and consulting rooms but also to involve family...

Antimicrobial resistance and PCR-ribotyping of Shigella responsible for foodborne outbreaks occurred in southern Brazil.

Little information about Shigella responsible for foodborne shigellosis is available in Brazil. The present study aimed to investigate the antimicrobial resistance and PCR-ribotyping patterns of Shigella isolates responsible for foodborne outbreaks occurred in Rio Grande do Sul State (RS), Southern Brazil in the period between 2003 and 2007. Shigella strains (n=152) were isolated from foods and fecal samples of victims of shigellosis outbreaks investigated by the Surveillance Service. Identification of the strains at specie level indicated that 71.1% of them were S. flexneri, 21.5% S. sonnei, and 0.7% S. dysenteriae. Ten strains (6.7%) were identified only as Shigella spp. An increasing occurrence of S. sonnei was observed after 2004. Most of the strains were resistant to streptomycin (88.6%), followed by ampicillin (84.6%), and sulfamethoxazole/trimethoprim (80.5 %). Resistant strains belonged to 73 patterns, and pattern A (resistance to ampicillin, sulfamethoxazole/trimethoprim, tetracycline, streptomycin, chloramphenicol, and intermediate resistance to kanamycin) grouped the largest number of isolates (n=36). PCR-ribotyping identified three banding patterns (SH1, SH2, and SH3). SH1 grouped all S. flexneri and SH2 grouped all S. sonnei. The S. dysenteriae strain belonged to group SH3. According to the results, several Shigella isolates shared the same PCR-rybotyping banding pattern and the same resistance profile, suggesting that closely related strains were responsible for the outbreaks. However, other molecular typing methods need to be applied to confirm the clonal relationship of these isolates.

Antimicrobial resistance and PCR-ribotyping of Shigella responsible for foodborne outbreaks occurred in southern Brazil

Little information about Shigella responsible for foodborne shigellosis is available in Brazil. The present study aimed to investigate the antimicrobial resistance and PCR-ribotyping patterns of Shigella isolates responsible for foodborne outbreaks occurred in Rio Grande do Sul State (RS), Southern Brazil in the period between 2003 and 2007. Shigella strains (n=152) were isolated from foods and fecal samples of victims of shigellosis outbreaks investigated by the Surveillance Service. Identification of the strains at specie level indicated that 71.1% of them were S. flexneri, 21.5% S. sonnei, and 0.7% S. dysenteriae. Ten strains (6.7%) were identified only as Shigella spp. An increasing occurrence of S. sonnei was observed after 2004. Most of the strains were resistant to streptomycin (88.6%), followed by ampicillin (84.6%), and sulfamethoxazole/trimethoprim (80.5 %). Resistant strains belonged to 73 patterns, and pattern A (resistance to ampicillin, sulfamethoxazole/trimethoprim, tetracycline, streptomycin, chloramphenicol, and intermediate resistance to kanamycin) grouped the largest number of isolates (n=36). PCR-ribotyping identified three banding patterns (SH1, SH2, and SH3). SH1 grouped all S. flexneri and SH2 grouped all S. sonnei. The S. dysenteriae strain belonged to group SH3. According to the results, several Shigella isolates shared the same PCR-rybotyping banding pattern and the same resistance profile, suggesting that closely related strains were responsible for the outbreaks. However, other molecular typing methods need to be applied to confirm the clonal relationship of these isolates.

Serotipos y resistencia antimicrobiana de cepas de Shigella flexneri aisladas de niños con diarrea aguda: Relación entre el serotipo y la severidad del episodio / Serotype and antimicrobial resistance of Shigella flexneri strains isolated from children with acute diarrhea: Relationship between serotype and severity of the episode

Se determinó el serotipo, susceptibilidad a los antimicrobianos y la relación de severidad de la infección con el serotipo, a un grupo de 50 cepas de S. flexneri aisladas de niños menores de 5 años con diarrea: 25 niños deshidratados y 25 no deshidratados. Para la tipificación se utilizaron antisueros comerciales y la susceptibilidad a los antimicrobianos se realizó por el método de difusión en disco. Características epidemiológicas y clínicas de los episodios: media de edad 13,32 meses ± 12, clase obrera y marginal 94% (P< 0,05), eutróficos 80% (P<0,05), sangre macroscópica en heces 82% (P< 0,05), vómitos 60% (P> 0,05). El serotipo con mayor frecuencia fue el 2a (40%), seguido por el 3a (24%), 2b (18%), 1a (6%), 6 (4%), 3b (2%), 4a (2%), variante “X” (2%) y variante “Y” (2%). El mayor porcentaje de resistencia se observó a tetraciclina (96%), seguido por ampicilina (94%), cloranfenicol (90%), amoxicilina ácido clavulánico (84%) y trimetoprin-sulfametoxazol (72%). La desnutrición (36%, P< 0,05) y el serotipo 2a (56%, P< 0,05) se observaron con mayor frecuencia en los niños deshidratados, mientras que el serotipo 2b predominó en los no deshidratados (32%, P< 0,05). La prevalencia del serotipo 2a, su asociación con la severidad del episodio y la elevada resistencia a los antibióticos alertan sobre la problemática de la infección por Shigella en el país y refuerza la necesidad de estudios para ajustar pautas en el tratamiento.

Serotype, antimicrobial susceptibility, and severity of the infection according to serotype, were determined in a group of 50 Shigella flexneri strains isolated from children less than 5 years old with diarrhea: 25 children dehydrated and 25 non dehydrated. Commercial antisera were used for serotyping and antimicrobial susceptibility was determined by the disc diffusion method. Clinical and epidemiological characteristics of the episodes: mean age 13.22 ± 12 months; 94% belonged to laborer and marginal classes (P<0.05); 80% eutrophic (P<0.05); 82% macroscopic blood in feces (P<0.05); 60% vomits (P>0.05). The most frequent serotype was 2a (40%), followed by 3a (24%), 2b (18%), 1a (6%), 6 (4%), 3b (2%), 4a (2%), variant “X” (2%) and variant “Y” (2%). The highest resistance percent was found for tetracycline (96%), followed by ampicylline (94%), chloramphenicol (90%), amoxicylline clavulonic acid (84%) and trimetoprim-sulfametoxazol (72%). Malnourishment (32%, P<0.05) and serotype 2a (56%, P<0.05) were seen more frequently in dehydrated children, while serotype 2b predominated in non dehydrated children (32%, P<0.05). Prevalence of serotype 2a and its association with the severity of the episode and high antibiotic resistance alert regarding the problem of Shigella infections in our country and reinforce the need of further studies to adjust treatment norms.