Identification of the nasopharyngeal carriage of Neisseria meningitidis by 16S rRNA Gene sequencing in asymptomatic adolescents and young adults in Cartagena, Colombia (2019-2020)

Abstract The bacterium Neisseria meningitidis, a strictly human pathogen, can cause meningitis, meningococcemia, sepsis, and death; repeatedly it scause outbreaks around the world. The frequency of asymptomatic carriage is often high in adolescents and young adults, increasing the invasive meningococcal disease risk and likelihood of transmission. However, detailed analyses of meningococcal carriage in this population in Colombia, particularly in coastal areas, are lacking. In this study, the prevalence and characteristics of Neisseria meningitidis carriage were evaluated in asymptomatic adolescents and young adults (11-25 years old) in Cartagena, Colombia. Oropharynx samples were collected from participants between August and December 2019. The phenotypic identification of bacteria was performed by conventional methods and biochemical testing. Molecular identification to the species level was performed by 16S rRNA gene sequencing. In total, 12 of 648 samples were positive for Neisseria meningitidis by 16S rRNA sequencing, indicating a prevalence of 1.9%. Isolates were classified into four invasive serogroups (A, B, C, and W) by a comparative sequence analysis of the ribosomal gene. Despite the occurrence of meningococcal disease in Cartagena city in the last several years, the frequency of oropharyngeal carriage in adolescents and young adults was low. Serogroup A had not been previously reported in nasopharyngeal samples in Colombia. This is the first report of Neisseria meningitidis on the Colombian Caribbean coast based on 16S rRNA sequencing and is expected to guide the development of vaccination and follow-up strategies.

Serogroups and antibiogram of Salmonella isolates from dairy cattle in Nkonkobe District, South Africa

Aims@#The use of antimicrobial agent for treatment or growth promotion has added burden to treat infection diseases caused by pathogenic bacteria as they can acquire resistance. Salmonella is one of the major zoonotic bacterial pathogens that acts as a potential reservoir of antimicrobial resistance elements. In this study, the presence of Salmonella serotypes and the antibiogram patterns of the isolates from fecal samples of healthy cows in some selected localities in Eastern Cape, South Africa were studied.@*Methodology and results@#Two hundred fecal samples were collected from healthy adult cows, of which 180 presumptive Salmonella isolates were recovered by conventional method. The isolates were identified using specific primer sets that are capable of detecting Salmonella spp. as well as delineating them into serogroups A, B, C1, C2, and D. Thereafter, antimicrobial susceptibility patterns of the identified isolates were determined by disk diffusion method against a panel of 12 antibiotics. From the molecular analysis of the isolates, 108 isolates were identified as Salmonella spp. and the confirmed isolates were further delineated into serogroup and the prevalence of the serogroups detected were 20%, 18%, 2%, 20% and 40% for serogroup A, B, C1, C2 and D respectively. Extremely high levels of antibiotic resistances were observed among the study isolates, while serogroup D was the most prevalent serogroup among the study isolates.@*Conclusion, significance and impact of study@#In conclusion, dairy cows could be considered as major reservoirs of antibiotic resistant Salmonella spp. that could be transmitted to humans via the food chain. This poses a significant public health risk especially to people living around the farms as well as those who consume poorly cooked meat and those who deal on raw cow meat.

Estandarización de una técnica de PCR múltiple para la detección de los serogrupos O157, O104 y "big six" de Escherichia coli productora de la toxina Shiga (STEC) / Standardization of a multiplex PCR technique for the detection of Shiga toxin-producing Escherichia coli (STEC) serogroups O157, O104 and "big six"

Los serogrupos O26, O45, O103, O104, O111, O121, O145 y O157 de STEC se relacionan con un elevado número de casos de SUH a nivel mundial, por lo que están incluidos dentro de las categorías de mayor riesgo para los humanos, según los criterios de autoridades alimentarias de Estados Unidos y Europa. El método convencional de identificación de antígenos O y H se realiza por aglutinación con antisueros de conejo. Este método además de ser muy costoso y laborioso, no se encuentra disponible en el país para empleo masivo. En este contexto, el objetivo de este estudio observacional descriptivo de corte transverso ha sido la estandarización de una técnica de PCR múltiple para la detección de estos 8 serogrupos, a fin de contar con un sistema de detección eficiente, sensible y con potencial de aplicación en la industria alimentaria. Se estandarizaron reacciones de PCR empleando como controles positivos cepas E. coli de referencia correspondientes a la totalidad de los serogrupos citados. Se obtuvieron productos de tamaños esperados para cada serogrupo, no se observaron amplificaciones cruzadas o falsos positivos. Esta técnica estandarizada podría representar una herramienta rápida y menos costosa que la técnica serológica, con la capacidad de ser aplicada a diferentes matrices, permitiendo la detección de estos serogrupos en aislados STEC de ganado en pie, fuentes de agua de consumo, alimentos e incluso en aislamientos clínicos asociados a enfermedades humanas(AU)

STEC serogroups O26, O45, O103, O104, O111, O121, O145, and O157, are related to a high number of cases of HUS worldwide, so they are included in the categories of greatest risk for humans, according to the food administration criteria of the United States and Europe. The conventional method of identifying antigens O and H is carried out by agglutination with rabbit antisera. This method is very expensive and laborious and is not available in the country for massive-scale use. In this context, the objective of this cross-sectional descriptive observational study has been the standardization of a multiplex PCR technique for the detection of these 8 serogroups, in order to have an efficient and sensitive detection system with the potential for application in the food industry. PCR reactions were standardized using as positive controls reference E. coli strains to correspond to all the mentioned serogroups. Products of expected sizes were obtained for each serogroup; no cross-amplification or false positives were observed. This standardized technique could represent a quick and less expensive tool than the serological technique, with the possibility to be applied to different kind of samples, allowing the detection of these serogroups in STEC isolates of live cattle, sources of drinking water, food and even in clinical isolates associated with human diseases(AU)

Epidemiología, clínica y factores pronósticos de Enfermedad Meningocóccica Invasora en un centro de referencia de Paraguay. 2005 a 2018

Resumen Introducción: La enfermedad meningocóccica ha sido y sigue siendo una causa importante de morbilidad y mortalidad. Objetivos: Analizar las características clínicas y epidemiológicas de pacientes con infección meningocóccica invasora hospitalizados en un centro hospitalario de referencia. Materiales y métodos: Estudio descriptivo, observacional y retrospectivo de revisión de historias clínicas de pacientes internados entre los años 2005 y 2018 en el Instituto de Medicina Tropical con aislamiento o detección de N. meningitidis en sangre o LCR. Resultados: Fueron captados 44 pacientes con enfermedad meningocóccica invasora durante el periodo estudiado (3±2 casos/año). Los casos predominaron en el grupo etario 15000 /mm3 (p=0,03), la plaquetopenia15000 /mm3, la leucopenia <5000/ mm3, y la plaquetopenia se asociaron a mayor mortalidad.

Abstract Introduction: Meningococcal disease has been and continues to be an important cause of morbidity and mortality around the world. Objectives: To analyze the clinical and epidemiological characteristics of patients with invasive meningococcal infection hospitalized in a reference hospital center. Materials and methods: A descriptive, observational and retrospective study based in the review of clinical records of patients admitted between 2005 and 2018 in the Institute of Tropical Medicine in whom Neisseria meningitidis was isolated o detected by PCR in blood or CSF. Results: Forty-four patients with invasive meningococcal disease were recruited during the period studied (3 ± 2 cases/year). The cases predominated in the age group 15000/mm3 (p=0.03), thrombocytopenia15,000/mm3, leukopenia <5000 / mm3, and thrombocytopenia were associated with increased mortality.

Serogroup identification, phenotypic detection of hemolysis and extended spectrum beta-lactamases of Escherichia coli isolated from psittacine of illegal wildlife trade in Fortaleza, Brazil / Identificação de sorogrupo e detecção fenotípica de betalactamase de espectro estendido e produção de hemolisina em Escherichia coli isoladas de psitacídeos do tráfico de animais silvestres em Fortaleza-CE

This study aimed to identify serogroups of Escherichia coli important for human health in isolates from psittacine of illegal wildlife trade in Ceará State. In addition, hemolysis and production of Extended Spectrum Beta-Lactamases (ESBL) was assessed in the isolates. A total of 78 E. coli strains isolated from different Psittaciformes species from a wildlife rehabilitation center in Fortaleza, Brazil. The isolates used in this study were previously identified and stored. Serogroup identification was performed using polyvalent sera for EPEC (O55, O111, O119, O114, O125, O86, O126, O127, O128), EIEC (O136, O124) and EHEC (O157). ESBL detection was performed with double disk synergy method. For hemolysis detection, isolates were inoculated in blood agar base enriched with ovine blood. Only 31 (39.7%) isolates were seropositive and the most frequent were O127, O114, O128 and O111. There was no agglutination for serogroups O55, O124, O136 or O157. Considering both seropositive and seronegative isolates, 9 (11.5%) and 35 (44.9%) presented hemolysis and ESBL production, respectively. In conclusion, the investigated psittacine from illegal wildlife trade hosted ESBL-producing E. coli strains and some belong to important serogroups often linked to severe human infections.(AU)

Este trabalho teve como objetivo identificar sorogrupos de E. coli importantes para a saúde humana, oriundos de psitacídeos provenientes do tráfico no estado do Ceará, assim como detectar atividade hemolítica e produção de betalactamase de espectro estendido (ESBL). Foram testadas 78 cepas de Escherichia coli provenientes de psitaciformes do Centro de Triagem de Animais Silvestres, Fortaleza, CE. Para a identificação dos sorogrupos, utilizaram-se soros polivalentes EPEC (O55, O111, O119, O114, O125, O86, O126, O127, O128), EIEC (O136, O124) e EHEC (O157). Para detecção de ESBL, as cepas foram submetidas ao método de aproximação de disco e, para a detecção de hemolisina, foram plaqueadas em ágar sangue base enriquecido com sangue de carneiro. No geral, 31 (39,7%) das amostras foram soropositivas. Os sorogrupos mais frequentemente detectados foram O127, O114, O128 e O111. Não houve positividade para os sorogrupos O55, O124, O136 e O157. Considerando-se as amostras sororreagentes e não sororreagentes, observou-se que nove (11,5%) e 35 (44,9%) cepas de E. coli apresentaram produção de hemolisinas e de ESBL, respectivamente. Em conclusão, constatou-se que psitacídeos provenientes do tráfico de animais silvestres albergam cepas de E. coli produtoras de ESBL e providas de importantes sorogrupos implicados em graves infecções humanas.(AU)

A Survey of Serum Bactericidal Antibodies against Neisseria meningitidis Serogroups A, C, W and Y in Adolescents and Adults in the Republic of Korea / 감염과화학요법

BACKGROUND: This descriptive epidemiological study aimed to assess the prevalence of serum bactericidal antibodies against Neisseria meningitidis serogroups A, C, W and Y in adolescents and adults in the Republic of Korea. MATERIALS AND METHODS: In total, 987 subjects aged 11-55 years from five geographical regions of Korea were included in the study. Human serum bactericidal assay (hSBA) was used to measure hSBA titres for serogroups A, C, W and Y. Percentages of subjects with hSBA titres ≥4 and ≥8, geometric mean titres (GMTs), and associated 95% confidence intervals (CIs), were estimated. Analysis was performed for the entire study population and stratified by age group or region. No statistical hypotheses were tested. RESULTS: The highest percentage of subjects with hSBA titres ≥8 was observed for serogroup W (74%), was similar for serogroups C (34%) and Y (36%), and was lowest for serogroup A (9%). The percentages of subjects with hSBA titres ≥4 were similar to those with hSBA titres ≥8 for all serogroups. GMTs were 2.56 µg/mL (serogroup A), 5.14 µg/mL (serogroup C), 22.63 µg/mL (serogroup W) and 5.28 µg/mL (serogroup Y). Similar trends in GMTs across serogroups were seen for individual regions and age groups. The highest GMTs for serogroups A, W and Y were recorded in the >19-29 years group, and for serogroup C in the >49-55 years group. Across all regions, GMTs were very similar for serogroups A, C and Y, while more variation was seen for serogroup W. CONCLUSION: In the Korean population, among Neisseria meningitidis serogroups A, C, W and Y, serum bactericidal antibodies were most prevalent against serogroup W and least prevalent against serogroup A. These trends were maintained across age groups and regions. The highest GMTs for serogroups A, W and Y were observed in the >19-29 years group. The reasons behind the observed differences in prevalence of bactericidal antibodies against the serogroups are currently not understood, although carriage and cross-reactivity of the assay may be important influences.

Group A rotavirus and bacterial agents associated with diarrhoea-induced hospitalisations in children below 5 years of age in Jammu.

Out of 210 faecal samples collected from children below 5 years attending different hospitals in Jammu and exhibiting clinical signs of diarrhoea, 41.9% samples were found positive for group A rotavirus by RNA-PAGE. Escherichia coli isolated in the study belonged to nine serogroups, out of which O69 was most frequent, being present in 12.38% samples. E. coli serogroups well recognised as enteropathogens viz. O69, O20 and O153 were present in 27.6% samples. Other bacterial pathogens associated with diarrhoea were present in 8.09% samples, out of which Shigella spp. was found in 4.76% samples followed by Salmonella spp. (2.38%) and Pseudomonas spp. (0.95%).

Characterization of Escherichia coli virulence genes, pathotypes and antibiotic resistance properties in diarrheic calves in Iran

BACKGROUND: Calf diarrhea is a major economic concern in bovine industry all around the world. This study was carried out in order to investigate distribution of virulence genes, pathotypes, serogroups and antibiotic resistance properties of Escherichia coli isolated from diarrheic calves. RESULTS: Totally, 76.45% of 824 diarrheic fecal samples collected from Isfahan, Chaharmahal, Fars and Khuzestan provinces, Iran were positive for E. coli and all of them were also positive for cnf2, hlyA, cdtIII, f17c, lt, st, stx1, eae, ehly, stx2 and cnf1 virulence genes. Chaharmahal had the highest prevalence of STEC (84.61%), while Isfahan had the lowest (71.95%). E. coli serogroups had the highest frequency in 1-7 days old calves and winter season. Distribution of ETEC, EHEC, AEEC and NTEC pathotypes among E. coli isolates were 28.41%, 5.07%, 29.52% and 3.49%, respectively. Statistical analyses were significant for presence of bacteria between various seasons and ages. All isolates had the high resistance to penicillin (100%), streptomycin (98.25%) and tetracycline (98.09%) antibiotics. The most commonly detected resistance genes were aadA1, sul1, aac[3]-IV, CITM, and dfrA1. The most prevalent serogroup among STEC was O26. CONCLUSIONS: Our findings should raise awareness about antibiotic resistance in diarrheic calves in Iran. Clinicians should exercise caution when prescribing antibiotics.

Development of both multiple PCR and real-time SYBR green PCR for the detection of Vibrio cholerae non-O1/O139 serogroups / 中华流行病学杂志

Objective To develop methodology of both multiple PCR and real-time SYBR green PCR for the detection of Vibrio cholerae (V.cholerae) serogroups non-O1 and non-O139.Methods The outer membrane protein gene (ompW) specific for V.cholerae,as well as O antigen rfb genes specific for both O1 and O139,were used for the design of the PCR primers.Both multiple PCR and real-time SYBR green PCR systems were used to detect both O1 and O139.Specific rfb genes and ompW were developed to evaluate their specificity,limit of detection,reproducibility and consistency.Results We established multiple PCR and real-time SYBR green PCR methods.According to the specific electrophoretic bands (multiple PCR) and the specific melt curve temperature (real-time SYBR green PCR),both methods could specifically detect the non-O1,non-O139 V.cholerae,and to differentiate them from O1,O139 V.cholerae,other five Vibrios and 3 intestinal bacteria.The detection limits were 7 × 104 cfu/ml (multiple PCR) and 7 × 102 cfu/ml (real-time SYBR green PCR),with statistically significant difference seen (P＜0.05).For the reproducibility of real-time SYBR green PCR,the external coefficient variation ranging from 0.22％ to 0.92％ while the internal coefficient variation ranging from 0.27％ to 1.41％.370 strains of non-O1,non-O139 V.cholerae,were detected,with both consistency rates as 100％.Conclusion Both multiple PCR and real-time SYBR green PCR could detect non-O1,non-O139 V.cholerae,rapidly,specifically,and reproducibly,that could all be used for the detection and identification of non-O 1,non-O 139 under different conditions.

Re-evaluation of the immunogenicity of meningococcal serogroups A and C polysaccharide vaccine among a healthy population aged 5 to 59 / 中华微生物学和免疫学杂志

Objective To re-evaluate the immunogenicity of meningococcal serogroups A and C polysaccharide vaccine among a healthy population of age 5 to 59.Methods Pre and post-vaccination ser-um samples were collected from the subjects involved in a randomized , controlled clinical trial conducted in 2005 at Hechi, Guangxi, China.Enzyme-linked immunosorbent assay (ELISA) was performed for the quan-titative detection of specific anti-capsule IgG antibody against meningococcal serogroups A and C in serum samples.Serum bactericidal assay ( SBA) was used to measure the bactericidal antibody activity against se-rougroups A and C bacterial strains .Results Geometric mean concentrations (GMCs) of specific anti-cap-sule IgG antibody were 23.66 μg/ml and 78.83 μg/ml for serogroup A (P0.05).The percentage of serum sam-ples with serogroup C-specific IgG concentration ≥2 μg/ml rose from 20%to 99% after vaccination ( P0.05), and from 14%to 96%for serogroup C (P<0.05) after vaccination.The rSBA GMTs with at least four times of in-creases after vaccination were detected respectively in 53% and 100% of serogroups A and C vaccinated subjects.Pearson correlation coefficient between IgG concentration and rSBA GMTs was r=0.15 (pre) and r=0.23 (post) for serogroup A, and r=-0.14 (pre) and r=0.58 (post) for serogroup C (P<0.05). Conclusion This study has demonstrated an efficient and sustained immunogenicity with meningococcal sero -groups A and C polysaccharide vaccine as evidenced by the data from standardized assays of ELISA and SBA .

Prevalência de sorogrupos de neisseria meningitidis causadores de doença meningocócica no estado da Bahia de 1998 a 2007 / Prevalence of neisseria meningitidis sorogroups that cause meningococcal disease in Bahia, from 1998 to 2007 / Prevalencia de serogrupos de n. meningitidis causadores de enfermedad meningocócica en el estado de la Bahia de 1998 a 2007

A Doença Meningocócica (DM), problema de saúde pública em razão da elevada morbidade e letalidade em nosso meio, tem preocupado devido à recente ascensão do sorogrupo C da N. meningitidis em detrimento do sorogrupo B, que apresenta maior potencial para causar epidemias, e ao possível surgimento de novo perfil epidemiológico da doença. O objetivo deste estudo é quantificar a prevalência dos sorogrupos de N. meningitidis causadores de DM no estado da Bahia nos últimos 10 anos. Este é um estudo descritivo que avalia casos notificados de DM na Bahia de 1998 a 2007, por sexo, idade, letalidade e sorogrupos causadores. Dos 2.070 casos de DM, foram sorogrupados 327 (34,4por cento). O sorogrupo B foi responsável por 71,9por cento dos casos e o C por 26,65por cento, entretanto foi verificada inversão da frequência a partir de 2006, com sorogrupo C representando 77,8por cento dos casos em 2007. Homens e menores de cinco anos foram mais acometidos e a letalidade em 2007 foi de 31por cento. Concluiu-se que, também na Bahia, ocorreu um aumento do sorogrupo C em detrimento do sorogrupo B, o que evidencia a mudança da prevalência do sorogrupo causador da doença meningocócica, fato que tem como consequencia a mudança no perfil epidemiológico da doença.

Meningococcal disease (MD) is a public health problem due to the high morbidity and mortality rate in our country. Recently, the rise of serogroup C of N. meningitidis serogroup B instead, worries due to the greater potential to cause epidemics of this group and the possible emergence of a new epidemiological pattern of disease. The aim of this study is to quantify the prevalence of serogroups of N. meningitidis causes of DM in the state of Bahia in the last 10 years. This is a descriptive study that evaluates reported cases of DM in Bahia from 1998 to 2007, by sex, age, cause lethality and serogroups. Of the 2,070 cases of DM were different serogroups 327 (34.4percent). The serogroup B accounted for 71.9percent of cases and 26.65percent for C, however the frequency was observed reversal from 2006, with serogroup C accounting for 77.8percent of cases in 2007. Men and children under five years were most affected and the mortality rate in 2007 was 31percent. It was concluded that, in Bahia, an increase of serogroup C at the expense of serogroup B, which shows the change in the prevalence of serogroup causing meningococcal disease, a fact that leads to change in the epidemiology of the disease.

Resumen La enfermedad meningocócica (ED) es un problema de salud pública debido a la alta morbilidad y mortalidad en nuestro medio. El reciente aumento del serogrupo C de N. meningitidis en detrimento del serogrupo B, ha despertado preocupación por su alto potencial de causar epidemias y al posible aparecimiento de un nuevo patrón epidemiológico. El objetivo de este estudio es cuantificar la prevalencia de los serogrupos de N. meningitidis causa de la ED en el estado de la Bahía, en los últimos 10 años. Es un estudio descriptivo que evalúa denuncias de casos de ED en la Bahía de 1998 a 2007, por sexo, edad, letalidad y serogrupos causadores de la enfermedad. De los 2.070 casos de ED, 327 (34,4por ciento) fueron seroagrupados. El serogrupo B representó el 71,9por ciento de los casos y el C, el 26,65por ciento, sin embargo, se observó reversión en la frecuencia a partir de 2006, con el serogrupo C representando el 77,8por ciento de los casos en 2007. 678 Los hombres y los niños menores de cinco años fueron los más afectados y la tasa de mortalidad en 2007 fue del 31por ciento. Se concluye que, también en el estado de la Bahía, hubo un aumento del serogrupo C, en detrimento del serogrupo B, lo que muestra el cambio en la prevalencia del serogrupo causador de la enfermedad meningocócica, hecho que tiene como consecuencia el cambio de patrón epidemiologico de la enfermedad.

Serotipos de Streptococcus pneumoniae en Cuba y progresión de la resistencia a la penicilina / Streptococcus pneumoniae serotypes in Cuba and progression of resistance to penicilina

INTRODUCCIÓN: en Cuba, a partir de 2006, ha sido difícil establecer la incidencia real de las meningitis bacterianas y otras enfermedades invasivas por Streptococcus pneumoniae, como consecuencia del bajo porcentaje de aislamiento e identificación de este agente en la red de laboratorios de microbiología del país. OBJETIVO: alertar sobre la necesidad de revitalizar la vigilancia activa de la enfermedad neumocócica invasiva, epidemiológica y microbiológica, fundamentalmente las meningitis y neumonías, en la etapa previa a la vacunación. MÉTODOS: se compararon la circulación de los serogrupos/serotipos capsulares y la susceptibilidad a penicilina de los aislamientos de S. pneumoniae responsables de infecciones invasivas, en dos períodos de la vigilancia: años 1994-2006 y 2007-2009. RESULTADOS: los serogrupos más frecuentes fueron: 3, 6, 7, 9, 14, 17, 18, 19, 20 y 23, pero se constató durante el segundo período de estudio, la circulación de otros no contenidos en las vacunas conjugadas disponibles comercialmente (serogrupo 15) y asociados a resistencia a antimicrobianos (serotipo 5). Por otra parte, se puso de manifiesto un incremento de la resistencia a la penicilina. CONCLUSIONES: para garantizar una alta efectividad con la inclusión en el calendario de vacunación infantil en Cuba, de alguna de las vacunas conjugadas contra S. pneumoniae, se impone el estudio de un número más representativo de aislamientos. Esto también permitirá hacer una correcta evaluación de la tendencia al incremento de la resistencia a la penicilina y adoptar guías de tratamiento adecuadas en el medio cubano.

INTRODUCTION: since 2006 in Cuba, there has been difficult to determine the actual incidente of bacterial meningitis and other invasive diseases caused by Streptococcus pneumoniae, as a result of the low percentage of isolation and identification of this agent in the domestic microbiology lab network. OBJECTIVE: to warn of the need of revitalizing the active surveillance of invasive, epidemiological and microbiological pneumoccocic diseases, mainly meningitis and pneumoniae in the phase prior to vaccination. METHODS: a comparison was made on the circulation of capsulary serogroups/serotypes and the invasive infection-causing S. pneumoniae isolates susceptibility to penicilline in two periods: 1994-2006 and 2007-2009. RESULTS: the most frequent serogroups were 3, 6, 7, 9, 14, 17, 18, 19, 20 and 23; however, in the second period, it was observed that others not contained in the available conjugate vaccines (serogrup 15) and associated to antimicrobial resistance (serotype 5) were circulating. On the other hand, increased resistance to penicilline was evident. CONCLUSIONS: it is required to study a more representative number of isolates in order to assure high effectiveness with the incorporation of some S. pneumoniae conjugate vaccines in the Cuban infant vaccination schedule. This will also allow duly assessing increased resistance to penicilline and adopting therapeutical guidelines suited to the Cuban setting.

Índice de patogenicidade, produção de hemolisina e sorogrupo de amostras de Escherichia coli isoladas de aves de postura comercial / Pathogenicity index, production of hemolysin and serogroup of samples of Escherichia coli isolated from commercial laying hens

Este estudo avaliou o índice de patogenicidade, a produção de hemolisina e a determinação de sorogrupos de cepas deEscherichia coli isoladas de fígado de aves de postura comercial com um dia de idade. Para este estudo, foram analisados 32 lotes, dos quais 15 foram positivos para o isolamento de E. coli no fígado, totalizando vinte e quatro amostras. A patogenicidade dos isolados foi determinada por inoculação no saco aéreo de pintinhos e classificada como alta, intermediária, baixa ou não-patogênica. Os sorogrupos foram identificados utilizando um conjunto de antissoros anti-O (O1 a O180). A produção de hemolisina foi determinada por semeadura em ágar sangue de galinha (8%) e em placas de ágar sangue de carneiro (8%). Do total de amostras estudadas, 17 (70,83%) foram classificadas como não patogênica, 6 (25%) como de baixa patogenicidade e 1 (4,17%) de alta patogenicidade. Foram identificados 14 sorogrupos diferentes: O1, O2, O5, O8, O15, O18, O22, O36, O64, O70, O75, O115, O132, O141. Cinco cepas não tiveram o sorogrupo identificado. Com relação ao teste de produção de hemolisina, todas as cepas foram consideradas negativas, tanto para o teste realizado com ágar sangue de galinha quanto para o de carneiro. Os resultados obtidos neste estudo demonstram a importância de se identificar as cepas prevalentes deE. colinas diferentes regiões produtoras, podendo ser utilizados em estudos epidemiológicos.

This work evaluated the index of pathogenicity, the production of hemolysin and determination of serogroups in Escherichia coli strains isolated from liver of commercial laying hens with one day of age. Thirtytwo lots were analyzed, of which 15 were positive for the isolation ofE. coli in the liver, for a total of 24 samples. The pathogenicity in one-day-old chicks was determined by inoculation in air sac and was classified as high, intermediate or low pathogenicity, or non-pathogenic. Serogroups were identified using a set of anti-O antisera (O1 to O180). The production of hemolysin was determined by plating on chicken blood agar (8%) and sheep blood agar (8%). Of the samples studied, 17 (70.83%) were classified as non-pathogenic, 6 (25%) as low pathogenicity and 1 (4.17%) as high pathogenicity. Fourteen different serogroups were identified: O1, O2, O5, O8, O15, O18, O22, O36, O64, O70, O75, O115, O132 and O141, while 5 samples were non-typable. Regarding the test for production of hemolysin, all strains were considered negative for both the test performed with chicken blood agar and that with sheep blood agar. The results of this study demonstrate the importance of identifying the prevalent strains of E. coli in different producing regions, as this information can be used in epidemiological studies.

Estudio seroepidemiológico de la leptospirosis humana en el departamento del Valle del Cauca, Colombia / Seroepidemiological situation of human leptospirosis in Valle del Cauca, Colombia

OBJETIVO: confirmar serológicamente la ocurrencia de leptospirosis humana en casos presuntivos procedentes del departamento del Valle del Cauca, estudiar variables clínico-epidemiológicas asociadas a la enfermedad e identificar los serogrupos de Leptospira más prevalentes en la región. MÉTODOS: se analizaron 150 muestras séricas colectadas en fase aguda, de casos con sospecha clínica y con riesgo epidemiológico de leptospirosis. Fueron evaluadas mediante hemoaglutinación indirecta y microaglutinación tomando como criterio de confirmación de la enfermedad la presencia de un título por microaglutinación mayor o igual que 1:800. Se analizaron datos epidemiológicos de interés así como síntomas y signos presentados en cada caso. RESULTADOS: las técnicas serológicas empleadas permitieron definir 31 casos confirmados (20,6 por ciento) y 16 casos probables (10,6 por ciento). Icterohaemorrhagie fue el serogrupo de mayor reactividad serológica tanto en casos confirmados como probables. Los síntomas más comunes fueron fiebre (89,3 por ciento), cefalea (86,7 por ciento) y mialgias (77,3 por ciento). Síntomas de leptospirosis severa como ictericia e insuficiencia renal fueron observados en 36 por ciento y 6,7 por ciento de los casos, respectivamente. Cerca de 70 por ciento de los casos confirmados o probables procedía de zonas urbanas y 85 por ciento resultó de hombres con un promedio de edad de 40 años. Los factores de riesgo más frecuentes fueron la exposición a roedores o animales domésticos (95,7 por ciento) y aguas potencialmente contaminadas (36,2 por ciento). CONCLUSIONES: los resultados del presente estudio sugieren que la leptospirosis constituye un problema de salud pública en el Valle del Cauca, región suroccidental de Colombia.

OBJECTIVE: to serologically confirm the occurrence of human leptospirosis in presumptive cases from the department of Valle del Cauca in Colombia, to study clinical-epidemiological data associated to the disease and to find out the most prevalent leptospiral serogroups. METHOD: a total of 150 serum samples collected during the acute phase from clinically suspected patients of having leptospirosis were analyzed. Samples were evaluated by indirect hemagglutination and microagglutination tests, taking a microagglutination titer equal to or greater than 1:800 as definition of confirmed case. Epidemiological data as well as symptoms and signs of interest were analyzed. RESULTS: these serological techniques allowed defining 31 confirmed cases (20.6 percent) and 16 probable cases (10.6 percent). Icterohaemorrhagiae was the serogroup with the higher serological reactivity in both confirmed and probable cases. Most common symptoms were fever (89.3 percent), headaches (86.7 percent) and myalgias (77.3 percent). Symptoms of severe leptospirosis like jaundice and renal failure were observed in 36 percent and 6.7 percent of cases, respectively. About 70 percent of confirmed or probable cases came from urban areas and 85 percent of them were men aged 40 years as average. The epidemiological risk factors were exposure to rats and domestic animal (95.7 percent) and potentially contaminated water (36.2 percent). CONCLUSIONS: the results of the present study suggest that leptospirosis is a public health problem in Valle del Cauca, a region located on the south west of the country.

Serogrupos y susceptibilidad antimicrobiana en cepas de Shigella / Serogroups and antimicrobial susceptibility in Shigella strains

Shigella spp es uno de los agentes causales más importantes de diarrea aguda en los niños. La presente investigación tuvo como objetivo conocer la frecuencia de serogrupos y la susceptibilidad antimicrobiana a los fármacos de elección y a los alternativos. MÉTODOS. Se realizó un estudio descriptivo y retrospectivo entre enero de 2004 y diciembre de 2006 a partir de 34 cepas de Shigella spp. aisladas en heces de niños menores de 5 años ingresados en el Hospital Aleida Fernández Chardiet (Municipio Güines) a causa de enfermedad diarreica aguda. RESULTADOS. Los serogrupos encontrados fueron S sonnei (70,5 por ciento) y S flexneri (29,5 por ciento). Ambos serogrupos mostraron altos niveles de resistencia al trimetoprim-sulfametoxazol y a la ampicilina, ademas en las cepas de S sonnei se encontró resistencia al ácido nalidíxico y en las de S flexneri al cloranfenicol. Todas las cepas mostraron altos porcentajes de sensibilidad a la ceftriaxona, norfloxacina y ciprofloxacina. El 70 por ciento de las cepas de S sonnei fueron multirresistentes. El patrón de multirresistencia (ampicilina, trimetoprim-sulfamtetoxazol y Acido nalidíxico) se encontró en ambos serogrupos. CONCLUSIONES. La determinación y vigilancia de los patrones de resistencia facilita el control de la política de uso de antibióticos en la región estudiada y previene el surgimiento de cepas resistentes a fármacos de nueva generación.

Shigella ssp. is one of the more important causal agents of acute diarrhea in children. Present research has as aim to know serogroups frequency and antimicrobial susceptibility to choice drugs, and to its alternatives. METHODS: A descriptive retrospective study was carried out between January 2004 and December 2006 of 34 strains of Shigella isolated from children lower than 5 years admitted in Aleida Fernßndez Chardiet Hospital in Güines Municipality by acute diarrheic disease. RESULTS: Serogroups included S sonnei (70,5 percent), and S flexeneri (29,5 percent). Both serogroups showed high levels of resistance to Trimethoprim-Sulfamethoxaxole and to Ampicillin and to in strains of S sonnei there was resistance to nalidixic acid, and in that of S flexeneri, to Chloramphenicol. All strains showed high percentages of sensibility to Cephtriaxone, Norphloxacine, and to Cyprophloxacine. The 70 percent of strains of S sonnei were multi-resistant. Multiresistance pattern (Ampicillin, Trimetroprim-Sulfamethoxaxole and nalidixic acid) was present in both serogroups. Assessment and surveillance of resistance patterns allow control of policy on use of antibiotics in study region, and to foresee rise of strains resistant to new generation-drugs.

Serogroups and virulence genotypes of Escherichia coli isolated from patients with sepsis

Sixty strains of Escherichia coli, isolated by hemoculture, from septicemic Brazilian patients were evaluated to determine their serogroup and invasivity to Vero cells. All 60 patients died within 2 days of hospitalization. Furthermore, the molecular study of the following extraintestinal pathogenic E. coli-associated virulence factor (VF) genes was performed by PCR: i) adhesins: type 1 fimbria (fimH), S fimbria (sfaD/E), P fimbria (papC and papG alleles) and afimbrial adhesin (afaB/C); ii) capsule K1/K5 (kpsMTII); iii) siderophores: aerobactin (iucD), yersiniabactin (fyuA) and salmochelin (iroN); iv) toxins hemolysin (hlyA), necrotizing cytotoxic factor type 1 (cnf1) and secreted autotransporter toxin (sat); v) miscellaneous: brain microvascular endothelial cells invasion (ibeA), serum resistance (traT), colicin V (cvaC) and specific uropathogenic protein (usp). Our results showed that isolates are able to invade Vero cells (96.6 percent), differing from previous research on uropathogenic E. coli (UPEC). The O serogroups associated with UPEC were prevalent in 60 percent of strains vs 11.7 percent of other serogroups. The PCR results showed a conserved virulence subgroup profile and a prevalence above 75 percent for fimH, fyuA, kpsMTII and iucD, and between 35-65 percent for papC, papG, sat, iroN, usp and traT. The evasion from the immunological system of the host and also iron uptake are essential for the survival of extraintestinal pathogenic E. coli strains. Interestingly, among our isolates, a low prevalence of VF genes appeared. Therefore, the present study contributes to the identification of a bacterial profile for sepsis-associated E. coli.

Sorogrupos de Escherichia coli enterotoxigênica isolada de coproculturas, no período de 1983 a 1987, no município de São Paulo / Enterotoxigenic Escherichia coli serogroups in isolates from stool cultures made from 1983 to 1987 in the municipality of Säo Paulo, Brazil

Durante o quinquênio 1983-1987 foram isoladas, na Seção de Bacteriologia do Instituto Adolfo Lutz, 87 cepas de Escherichia coli enterotoxigênica, a partir 5629 coproculturas. A média percentual de positividade nestes 5 anos foi de 1,54%. Entre as 87 cepas produtoras de toxina termoestável, 31(35,63%) produziram também toxina termolábil, com relação ao antígeno fator de colonização I e II (antígeno fimbriado F2 e F3), 43 (49,43%) cepas apresentaram um desses fatores. A utilização de 33 soros somáticos permitiu a identificação sorológica de 61 (70,11%) das 87 cepas estudadas. Os sorogrupos 0:6, 0:153, 0:78, 0:27 e 0:139 foram os mais frequentes (AU).

Estudo comparativo da sensibilidade da Neisseriameningitidis, sorogrupos A e C, à sulfadiazina, mediante emprego de discos e de concentrações variadas de sulfadiazina em meio sólido / Comparative study of the sensitivity of Neisseriameningitidis, serogroups A and C, to sulfadiazine, using discs and different concentrations of sulfadiazine in solid medium

No boletim nº 588 da OMS, série de Comunicações Técnicas sobre "A luta contra a meningite cérebro-espinhal", 1976, é aconselhada a pesquisa contínua da sensibilidade da Neiseeria meningitidis aos sulfamídicos e recomendada também a exposição da cepa a concentrações crescentes de sulfadiazina incorporada ao meio ágar-Mueller-Hinton, nas quantidades de 0,1; 1,0; 5,0 e 10 mg%. Neste trabalho foi empregada a técnica descrita por H. A. Feldman (1967), que utiliza as concentrações especificadas pela" OMS. Foram testadas 200 cepas de Neieeeriá meningitidis, sendo 100 do sorogrupo A e 100 do sorogrupo C, sendo verificada, simultaneamente, a sensibilidade das cepas à sulfadiazina em discos procedentes dos Laboratórios Difco, U.S.A., impregnados com 0,3 mg% do quimioterápico, segundo o método de Bauer, Kirby et alii (AU).

Avaliação da resposta imunológica em animais quando inoculados com Neisseria Miningitidis dos grupos "A"e "C" / Evaluation of the immune response in animals when inoculated with Neisseria Miningitidis from groups "A" and "C"

Para o estudo do comportamento da resposta imune Neisseria Meningitidis dos grupos "A"e "C, fora feitas inoculação em quarenta coelhos e quatro carneiros, com bacterias vivas e mortas, bem como com polissacarídeos especificos dos grupos A e C com ou sem adjuvante, em diferentes doses e vias de inoculação. Foram feitas várias séries de inoculações para verificar o efeito secudário e terciário da resposta, bem como tipo de anticorpos envolvidos. O nível de anticorpos e a permanencia dos mesmos no soro foi medido através da reação de hemaglutinação passiva e da imunoeletroforese cruzada; esta última técnica foi utilizada nestes soros para detecção de antigenos polissacarídicos de N. animais quando com Meningitidis. A análise dos resultados obtidos mostra que não existe diferença nas respostas imunes, nas concentrações variadas de 5,6 x 107 a 2,4 x 10 10 bactérias por coelhos. Os anticorpos, tanto (AU).