Significación de los marcadores infecciosos para identificar portadores de hepatitis B en donantes de sangre / Significance of hepatitis B surface antigen, IgM/IgG core antibody and hepatitis B virus DNA in blood donors

Resumen Introducción: La identificación de portadores del virus de la hepatitis B en donantes de sangre es imperativo para evitar la transmisión de la enfermedad a través de transfusiones sanguíneas. Objetivo: Determinar si los donantes de sangre con resultados positivos de los marcadores serológicos HbsAg y anti-HBc eran portadores de ADN del virus de la hepatitis B. Métodos: Se recolectaron 12 745 muestras de seis bancos de sangre ecuatorianos, las cuales fueron analizadas con pruebas serológicas para identificar los marcadores infecciosos HBsAg, anti-HBc, anti-HBs mediante prueba ELISA automatizada. Todas las muestras positivas para uno, dos o los tres marcadores fueron analizadas con técnica molecular para determinar la presencia de ADN viral. Resultados: Se identificó que 27.5 % de las muestras reactivas solo a anti-HBc y 100 % de las muestras con resultados positivos de HBsAg/anti-HBc-IgM/IgG presentaron ADN del virus de la hepatitis B (p = 0.001). Conclusiones: La elección de los marcadores de infección y los métodos de detección definen los resultados. Es importante la realización de dos pruebas serológicas y una molecular para identificar a los portadores del virus de la hepatitis B y evitar su transmisión.

Abstract Introduction: Identification of hepatitis B virus carriers in blood donors is imperative in order to avoid transmission of the disease via blood transfusion. Objective: To determine if blood donors with positive results for serological markers HBsAg and anti-HBc were hepatitis B virus DNA carriers. Methods: 12,745 samples were collected from six Ecuadorian blood banks and analyzed for HBsAg, anti-HBc and anti-HBs infectious markers by automated ELISA. All samples that tested positive for one, two or all three markers were analyzed with molecular techniques to determine the presence of viral DNA. Results: 27.5 % of the samples that were reactive for anti-HBc alone and 100 % of those with positive results for HbsAg and IgM/IgG anti-HBc were identified to contain hepatitis B virus DNA (p = 0.001). Conclusions: The selection of infection markers, as well as the detection methods define the results. Performing two serological and one molecular test is important in order to identify hepatitis B virus carriers and prevent its transmission.

Testagem de rastreio e busca ativa de infectados assintomáticos pelo SARS-COV-2: avisão do planejamento em saúde pública / Screening testing and active search for asymptomatic infected by SARS-COV-2: public health planning warning

Este artigo, tem como objetivo descrever evidências científicas da testagem para rastreamento de casos assintomáticos de Coronavírus. Examinaram-se artigos científicos, recomendações da Organização Mundial de Saúde e publicações em jornais. Conclui-se pela necessidade de adoção desta medida para o controle da pandemia e aponta-se para questões a serem respondidas para o planejamento do sistema de saúde. (AU)

Búsqueda de infección por Hepatitis B en familiares de portadores crónicos de la provincia de Huanta, Ayacucho -Perú / Search of Hepatitis-B infection in relatives of chronic carriers in the province of Huanta, Ayacucho, Peru

RESUMEN Un plan de eliminación del virus de hepatitis B (HBV) es factible porque la inmunización ha tenido buen impacto, tal como ha sucedido en la provincia de Huanta en Perú. El objetivo de nuestro estudio fue determinar la frecuencia de la infección por HBV en familiares de portadores del antígeno de superficie del virus de la hepatitis B (HBsAg). Este estudio transversal incluyó a 39 familiares de portadores crónicos, identificados en el Hospital de Apoyo de Huanta. Se recolectaron datos sociodemográficos y muestras de sangre. La frecuencia total de infección por HBV fue de 10,3 % y la mayoría correspondía a infección crónica (7,7 %). Una tercera parte tenía antecedentes de infección por HBV. Los miembros de la familia con infección por HBV fueron mayormente adultos alcohólicos y no vacunados. En conclusión, encontramos una alta frecuencia de HBV en familiares de portadores de HBsAg, esta estrategia ayudaría a identificar portadores crónicos que pueden ser tratados y contribuir a un plan de eliminación de HBV.

ABSTRACTS A plan of elimination of the virus of B hepatitis (HBV) is feasible because the immunization has had good impact, as it has been documented in the province of Huanta in Peru. The objective of our study was to determine the frequency of the infection by HBV in relatives of carriers of the surface antigen of the virus of hepatitis B (HBsAg). This cross-sectional study included 39 relatives of chronic carriers, identified at Hospital de Apoyo de Huanta. Sociodemographic data and blood samples were collected. The total frequency of infection by HBV was 10.3%, and the majority corresponded to chronic infection (7.7%). One third had a history of infection by HBV. The family members with HBV infection were mainly adult alcoholics who had not been vaccinated. In conclusion, we found a high frequency of HBV in relatives of carriers of HBsAg. This strategy would help identify chronic carriers that can be treated and to contribute to a plan for the elimination of HBV.

Unrecognized pediatric and adult family members of children with acute brucellosis

Abstract Background and aim Brucellosis is an infectious, contagious and zoonotic disease that occurs worldwide. The family members of an index case of brucellosis may be especially susceptible, due to sharing the same source of infection and similar risk factors for brucellosis. In this study, we propose to screen pediatric and adult family members of brucellosis index cases for detecting additional unrecognized infected family members. Materials and methods 114 family members of 41 pediatric patients with brucellosis were evaluated. All family members completed a brief questionnaire and were tested by a standard tube agglutination test (STA). Results The majority of family members (n = 96, 84.2%) were children. Among the 114 family members, 42 (36.8%) were seropositive, and 15 (35.7%) were symptomatic. The majority of the symptomatic seropositive family members (n = 12, 80%) had STA titers (≥1:640) higher than asymptomatic seropositive family members (n = 9, 33%; p = 0.004). Conclusion The routine screening of both pediatric and adult family members of index cases is a priority in endemic areas. Using this screening approach, unrecognized family members who are seropositive for brucellosis will be identified earlier and be able to receive prompt treatment.

¿Puede considerarse portadores asintomáticos a los donantes de sangre seropositivos para Trypanosoma cruzi?: un estudio de validación en el proyecto CHICAMOCHA / Can Seropositive Blood Donors be Considered Asymptomatic Carriers for Trypanosoma cruzi?: a validation study in CHICAMOCHA project / Poderiam ser considerados portadores assintomáticos os doadores de sangue soropositivos para Trypanosoma cruzi? um estudo de validação no projeto CHICAMOCHA

Identificar el deterioro clínico de individuos seropositivos para la enfermedad de Chagas requiere observar la evolución de personas con infección establecida por Trypanosoma cruzi (T.cruzi), libres de signos y síntomas de cardiomiopatía en una línea de base. Objetivo: Realizar una comparación entre donantes de bancos de sangre de Bucaramanga con serología positiva y negativa para T. cruzi. Metodología: La muestra consistio en donantes elegibles con pruebas de tamización positivas para T. cruzi, pero negativas para otros agentes infecciosos tamizados por los bancos de sangre. Estos registros fueron apareados con una muestra aleatoria 1:4 de donantes con pruebas negativas a todas las pruebas de tamizaci¾n. Los participantes fueron entrevistados para conocer aspectos sociodemográficos y de percepción de su estado de salud, se realizó examen físico y se tomaron muestras de sangre para examenes paraclínicos. Se reportaron las frecuencias y proporciones de los participantes. Se hicieron pruebas de hipótesis de no diferencias entre los dos grupos con la prueba Chi cuadrado, con un nivel alfa de significancia de 5%. Resultados: La muestra consistió en 2,132 donantes de sangre incluidos entre mayo de 2000 y marzo de 2004. Mediante prueba serológica se identificaron 488 (22.9%) seropositivos y 1644 (77.1%) seronegativos. Los seropositivos fueron mayores en edad, presentaron indicadores socioeconómicos menos favorables y menor afiliación a seguridad social con el régimen contributivo y tenÝan una mejor percepción de su salud en comparación con los seronegativos (p<0.05). No se observaron diferencias estadísticamente significativas en cuanto a la percepción del funcionamiento de los tres sistemas evaluados (cardiovascular, urinario y gastrointestinal) en ambos grupos.

In order to identify the clinical deterioration of seropositive individuals for Chagas disease, it is necessary to observe the evolution of people infected by Trypanosoma cruzi (T. cruzi), who do not show signs and symptoms of cardiomyopathy on a baseline. Objective: To compare blood donors with positive and negative serology for Trypanosoma cruzi in the city of Bucaramanga. Methodology: The sample consisted of eligible donors with positive screening tests for T. cruzi, but negative for other infectious agents screened by blood banks. These records were matched with a random sample 1: 4 donors who showed negative results to all the screening tests. Participants were interviewed to know their socio-demographic aspects and to get a perception of their health status. Physical exams were performed and blood samples were taken for laboratory tests. Frequencies and proportions of participants were reported. Hypothesis testing of no differences between the two groups using the Chi square test was performed, showing a 5% level of alpha significance. Resultados: The sample included 2132 blood donors between May 2000 and March 2004. By using serological tests, it was identified that 488 (22.9%) were seropositive and 1644 (77.1%) were seronegative. Seropositive donors were older people who belonged to a low socio-economic level and had no health insurance. They also had a better perception of their health compared to seronegative donors (p <0.05). The perception of how the three evaluated systems worked (cardiovascular, urinary and gastrointestinal) showed no statistically significant differences between the two groups. Conclusions: The study findings allow us to infer that seropositive blood donors for T. cruzi could be considered as asymptomatic carriers without clinical evidence of cardiomyopathy.

Para identificar o deterioro clínico dos indivíduos soropositivos para a doença de Chagas Ú necessério acompanhar a evolução de indivíduos com infecção estabelecida pelo Trypanosoma cruzi (T. cruzi), livres de sinais e sintomas de cardiomiopatia numa linha de base. Objetivo: Fazer uma comparação entre os doadores dos bancos de sangue de Bucaramanga com sorologia positiva e negativa para T. cruzi. Metodologia: A amostra consistiu de doadores elegíveis com rastreamento positivo para T. cruzi, porém negativo para outros agentes infecciosos selecionados pelos bancos de sangue. Esses registros foram emparelhados com uma amostra aleatória de 1: 4 com testes negativos a todos os testes da triagem de doadores. Os participantes foram entrevistados para se conhecer aspectos sociodemográficos e perceber seus aspectos de saúde, foi realizado um exame físico e foram coletadas amostras de sangue para exames de laboratório. Relataram-se as frequéncias e proporções de participantes. Foi feito um teste de hipóteses de não diferenças entre os dois grupos com o teste do chi-quadrado, com um nível alfa de significãncia de 5%. Resultados: A mostra consistiu em 2132 doadores de sangue incluídos entre maio de 2000 e marþo de 2004. Pela prova sorol¾gica identificaram-se 488 (22.9%) soropositivos y 1644 (77.1%) soronegativos. Os Soropositivos foram maiores de 18 anos, tinham indicadores socioeconómicos menos favoróveis, menor inscrição no seguro social com o regime contributivo e melhor percepção da sua saúde em relação aos soronegativos (p <0,05). Estatisticamente não se observaram diferenças significativas quanto Ó percepção do funcionamento dos trés sistemas avaliados (cardiovascular, gastrointestinal e urinário) em ambos os grupos. Concluções: resultados do estudo permitem concluir que os doadores soropositivos para T. cruzi no sangue poderiam ser vistos como portadores assintomáticos, sem evidência clínica de cardiomiopatia.

¿Es realmente asintomático el portador de la hemoglobina S? / Is hemoglobin s carrier really asymptomatic?

La controversia sobre si el estado de portador de la hemoglobina S debe ser visto como una enfermedad benigna o como un fenotipo intermedio de la anemia de células falciformes se mantiene hasta nuestros días. Los reportes de complicaciones renales, tromboembólicas y de muerte súbita relacionadas con el ejercicio en estos individuos, demandan la necesidad de un consenso en relación con este concepto. Nuestro objetivo es dirigir la atención hacia este grupo de personas que presentan una afectación genética de la síntesis de hemoglobina, identificar y detectar tempranamente complicaciones derivadas de esta condición genética, con el fin de proporcionarles una mejor atención médica y contribuir a definir si realmente el portador de la hemoglobina S es asintomático(AU)

Controversy over whether sickle cell trait should be considered as a benign disease or as an intermediate phenotype of sickle cell anemia has remained to this day. Reports of renal complications and sudden death associated to exercise in these individuals as well as thromboembolic complications demand the need for consensus regarding this concept. It is our goal with this paper to draw attention to this group of individuals, identifying and detecting early complications of their genetic condition in order to provide better health care and actually help to define whether or not sickle cell trait is asymptomatic in carriers(AU)

Influence of the socioeconomic status on the prevalence of malocclusion in the primary dentition

OBJECTIVE: To assess the influence of socioeconomic background on malocclusion prevalence in primary dentition in a population from the Brazilian Amazon. METHODS: This cross-sectional study comprised 652 children (males and females) aged between 3 to 6 years old. Subjects were enrolled in private preschools (higher socioeconomic status - HSS, n = 312) or public preschools (lower socioeconomic status - LSS, n = 340) in Belém, Pará, Brazil. Chi-square and binomial statistics were used to assess differences between both socioeconomic groups, with significance level set at P < 0.05. RESULTS: A high prevalence of malocclusion (81.44%) was found in the sample. LSS females exhibited significantly lower prevalence (72.1%) in comparison to HSS females (84.7%), particularly with regard to Class II (P < 0.0001), posterior crossbite (P = 0.006), increased overbite (P = 0.005) and overjet (P < 0.0001). Overall, malocclusion prevalence was similar between HSS and LSS male children (P = 0.36). Early loss of primary teeth was significantly more prevalent in the LSS group (20.9%) in comparison to children in the HSS group (0.9%), for both males and females (P < 0.0001). CONCLUSION: Socioeconomic background influences the occurrence of malocclusion in the primary dentition. In the largest metropolitan area of the Amazon, one in every five LSS children has lost at least one primary tooth before the age of seven. .

OBJETIVO: avaliar a influência da condição socioeconômica na prevalência de má oclusão na dentição decídua em uma população amazônica. MÉTODOS: esse estudo transversal compreendeu 652 crianças, de ambos os sexos, entre 3 e 6 anos de idade. Os indivíduos estavam matriculados na pré-escola na rede privada de ensino (alto nível socioeconômico; n = 312) ou, rede pública (baixo nível socioeconômico; n = 340), em Belém, no Pará. O teste chi-quadrado e estatística binominal foram usados para avaliar as diferenças entre os grupos socioeconômicos, com nível de significância considerado em p < 0,05. RESULTADOS: foi observada uma alta prevalência de má oclusão (81,44%) na amostra examinada. As meninas das escolas públicas exibiram uma prevalência significativamente menor (72,1%) em comparação às das escolas privadas (84,7%), principalmente com relação à prevalência da má oclusão de Classe II (p < 0,0001), mordida cruzada posterior (p = 0,006), sobremordida (p = 0,005) e sobressaliência (p < 0,0001). De maneira geral, a prevalência de má oclusão foi similar entre as crianças do sexo masculino dos dois grupos (p = 0,36). A perda precoce de dente decíduo foi significativamente mais prevalente no grupo com menor nível socioeconômico (20,9%) quando comparada à de crianças nas escolas privadas (0.9%), em ambos os sexos (p < 0,0001). CONCLUSÃO: a condição socioeconômica influencia a ocorrência de má oclusão na dentição decídua. Na maior metrópole da Amazônia, uma em cada cinco crianças do grupo com baixo nível socioeconômico perdeu, no mínimo, um dente decíduo antes dos sete anos. .

Importancia del diagnóstico de portadoras en familias con antecedentes de hemofilia / Importance of the diagnosis of carriers in families with history of hemophilia

La hemofilia es una enfermedad hemorrágica hereditaria ligada al cromosoma X que se presenta debido a mutaciones en los genes del factor VIII (hemofilia A) y el factor IX (hemofilia B), que ocasiona una disminución o deficiencia funcional de estas proteínas en plasma. Sus frecuencias son de 1 en 5 000 y 1 en 30 000 varones recién nacidos vivos, respectivamente. Afecta casi exclusivamente a los varones y las mujeres portadoras presentan un riesgo del 50 por ciento de transmitir la enfermedad a sus hijos, por lo que es importante en las familias con antecedentes de hemofilia identificar las portadoras a través de las consultas de asesoramiento genético, en el cual se brinda información acerca de la enfermedad, la confección del árbol genealógico, el cálculo del riesgo de recurrencia, el diagnóstico molecular y la posibilidad de diagnóstico prenatal en gestantes portadoras. Es imprescindible que el asesoramiento genético constituya un proceso educativo e informativo, nunca impositivo

Hemophilia is a hereditary bleeding disorderX-linked that a rises dueto mutations in the genes offactor VIII(hemophiliaA)andfactor IX(hemophiliaB), which causes a decrease orfunctional deficiency of these proteins inplasma.Their frequencies are 1 in5 000 males and1 in30 000 live births, respectively. It affects males almost exclusively, and female carriers have a50 percent risk of transmitting the disease to their children. So, it is important in families with history of hemophilia that carriers are identified through genetic counseling, which provides information about the disease, making pedigree,calculation of the risk of recurrence, molecular diagnosis and possibility of prenatal diagnosis in pregnant carriers.It is imperative that genetic counselingconstitutes an educational and informative process,never as an imposition

Prevalência de lesões cervicais não cariosas e da hiperestesia dentinária em alunos de Odontologia / Prevalence of non-carious cervical lesions and dentin hypersensitivity in Odontology students

O objetivo deste estudo foi determinar a prevalência de lesões cervicais não cariosas (LCNCs) e de hiperestesia dentinária em estudantes do curso de Odontologia da Universidade Estadual de Maringá (UEM) e registrar as variáveis bucais, comportamentais e sistêmicas comuns aos pacientes portadores, Foram examinados 80 alunos, utilizando um questionário como instrumento de coleta de dados. O exame clínico foi utilizado para verificar a presença de lesões na face vestibular de pré-molares e primeiros molares de todos os quadrantes, além da hiperestesia dentinária. A análise estatística foi analisada através do teste qui-quadrado com nível de significância de 5%. 77,5% apresentaram LCNCs, com média de 2,5 ± 2,8. O dente mais acometido foi o 1° pré-molar seguido do 2° pré-molar e do 1° molar. Quanto à hiperestesia dentinária houve diferença estatisticamente significante em um único elemento dentário (p=0,00540). Idade, hábitos parafuncionais, tipo de escova dental e dieta ácida não apresentaram relação com a presença das LCNCs. Assim, a ocorrência das LCNCs não pode ser atribuida a um único fator etiológico.

The aim of this study was to determine the prevalence of non-carious cervicallesions (NC-CLs) and dentin hypersensitivity in Odontology students of the State University of Maringá (UEM) and correlate them to variables oral, behavioral and systemic. Data of 80 students were collected via a questionnaire and clinical examination. The clinical examination was used to verify the dentin hypersensitivity and the presence of lesions on the buccal surface of premolars and first molars. Statistical analysis was performed by chi-square test at 5% significance level. 77,5% had NCCLs, with mean of 2.5 ± 2.8. The teeth with most NCCLs were the first premolar, foliowed by second premolar and then first molar. The dentin hypersensitivity was statistical in a single tooth (p = 000540). No significant diference for age, parafunctional habits, type of toothbrush and acidic diet, between the groups with or without NCCLs. Thus, the occurrence of NCCLs cannot be attributed only to a single etiological factor.

Submicroscopic malaria parasite carriage: how reproducible are polymerase chain reaction-based methods?

The polymerase chain reaction (PCR)-based methods for the diagnosis of malaria infection are expected to accurately identify submicroscopic parasite carriers. Although a significant number of PCR protocols have been described, few studies have addressed the performance of PCR amplification in cases of field samples with submicroscopic malaria infection. Here, the reproducibility of two well-established PCR protocols (nested-PCR and real-time PCR for the Plasmodium 18 small subunit rRNA gene) were evaluated in a panel of 34 blood field samples from individuals that are potential reservoirs of malaria infection, but were negative for malaria by optical microscopy. Regardless of the PCR protocol, a large variation between the PCR replicates was observed, leading to alternating positive and negative results in 38% (13 out of 34) of the samples. These findings were quite different from those obtained from the microscopy-positive patients or the unexposed individuals; the diagnosis of these individuals could be confirmed based on the high reproducibility and specificity of the PCR-based protocols. The limitation of PCR amplification was restricted to the field samples with very low levels of parasitaemia because titrations of the DNA templates were able to detect < 3 parasites/µL in the blood. In conclusion, conventional PCR protocols require careful interpretation in cases of submicroscopic malaria infection, as inconsistent and false-negative results can occur.

Portación y caracterización de Staphylococcus aureus en manipuladores de alimentos / Carriage and characterization of Staphylococcus aureus in food handlers

Staphylococcus aureus es una causa de intoxicaciones alimentarias por su capacidad de producir enterotoxinas. Los manipuladores de alimentos que portan S. aureus productores de enterotoxinas pueden provocar intoxicaciones alimentarias. Se estudiaron muestras tomadas de fosas nasales de 88 manipuladores de alimentos en la provincia de Misiones. El 37,5 % de los individuos analizados eran portadores de S. aureus. Mediante técnicas de amplificación (PCR), se detectaron genes que codifican la producción de enterotoxinas en 13 de los 33 aislamientos obtenidos (39,4 %) y en el 14,7 % de los manipuladores. De estos aislamientos, 10 portaban el gen sea y 3 el gen sec. El estudio de sensibilidad a los antibióticos mostró un 100 % de sensibilidad a teicoplanina, gentamiclna y rifampicina; 2 aislamientos fueron resistentes a clindamicina y a eritromicina y 4 resultaron resistentes a la meticilina. Estos resultados son un alerta e indicarían la necesidad de desarrollar medidas racionales para reducir el riesgo potencial de intoxicaciones alimentarias.

Staphylococcus aureus causes food poisoning due to its ability to produce enterotoxins. Food handlers carrying enterotoxin-producing S. aureus can contaminate food, thus leading to food poisoning. Samples were obtained from 88 food handlers in the Province of Misiones, Argentina. S. aureus was isolated from nasal swaps and PCR amplification was performed for genes encoding staphylococcal enterotoxins. A total of 37.5 % food handlers were positive for S. aureus. Expression of enterotoxin genes was found in 13 of the 33 (39.4 %) S. aureus isolates studied, accounting for 14.7 % of food handlers. Gene sea was detected in 10 isolates followed by gene sec in 3 isolates. All isolates were susceptible to teicoplanin, gentamicin and rifampicin. Four isolates were resistant to methicillin whereas 2 isolates were resistant to clindamycin and erythromycin. These results constitute a critical alert and indicate the need for developing rational measures to reduce the potential risk of food poisoning.

Critical analysis of cystic echinococcosis control programs and praziquantel use in South America, 1974-2010 / Análisis crítico de los programas de control de la equinococosis quística y uso del prazicuantel en América del Sur, 1974-2010

Cystic echinococcosis (CE) is one of the most prevalent zoonoses in Argentina, Brazil, Chile, Peru, and Uruguay. Control programs in South America were originally modeled after programs developed in insular territories, such as Tasmania and New Zealand. The advent and proven effectiveness of praziquantel, plus the experience of insular models, produced high expectations for rapid advances; however, after 30 years of praziquantel use, no endemic area in South America has obtained eradication. In fact, only modest gains in CE control have been made and impact on prevalence among humans has been slight. A major impediment has been the infrastructure needed to administer praziquantel to dogs in rural areas 8 times per year over numerous years, a requirement for rapid attack stage 1. Such an infrastructure has not been financially or politically sustainable in endemic areas, which tend to be the poorest. On the other hand, certain areas in Argentina have had success with simple and economically viable alternatives. Based primarily on continuous field work supported by the local community, these strategies have significantly decreased transmission to humans, the health sector's main objective. In addition, new possibilities and tools, such as the EG95 vaccine, are being evaluated; as are early detection and treatment of asymptomatic carriers.

La equinococosis quística (EQ) es una de las zoonosis más prevalentes en Argentina, Brasil, Chile, Perú y Uruguay. Los programas de control en América del Sur fueron originalmente hechos a imitación de los programas desarrollados en territorios insulares, como Tasmania y Nueva Zelandia. El advenimiento y la eficacia comprobada del prazicuantel, sumados a la experiencia de los modelos insulares, dieron lugar a altas expectativas de adelantos rápidos; sin embargo, después de 30 años de uso del prazicuantel, ninguna zona endémica en América del Sur ha logrado la erradicación de la enfermedad. De hecho, solo se han obtenido avances moderados en el control de la EQ, y su repercusión sobre la prevalencia en seres humanos ha sido leve. Un impedimento mayor ha sido la infraestructura necesaria para administrar el prazicuantel a los perros en zonas rurales 8 veces por año durante varios años, un requisito para el estadio 1 de ataque rápido. Tal infraestructura no ha sido sostenible desde el punto de vista económico o político en las zonas endémicas, que tienden a ser las más pobres. Por otro lado, ciertas áreas de la Argentina han tenido éxito con opciones sencillas y económicamente viables. Basadas principalmente en el trabajo continuo en el terreno apoyado por la comunidad local, estas estrategias han reducido significativamente la transmisión a los seres humanos, que es el objetivo principal del sector de la salud. Además, se están evaluando nuevas posibilidades y herramientas, como la vacuna EG95, al igual que la detección temprana y el tratamiento de los portadores asintomáticos.

Evaluation of culture and pcr methods for diagnosis of group b streptococcus carriage in Iranian pregnant women

Group B streptococcus [GBS] is one of the most important cause of morbidity and mortality among newborns especially in developing countries. It has been shown that the screening approach rather than the identification of maternal clinical risk factors for early-onset neonatal GBS disease is more effective in preventing early-onset GBS neonatal disease. The objective of this study was to detect GBS among clinical samples of women using PCR and standard microbiological culture. Samples were taken from 375 women at 28-38 weeks of gestation during six month from January 15 till June 15, 2011 from a hospital in Tehran, Iran. Samples were tested by standard culture using Todd- Hewitt broth, blood agar and by PCR targeting the cfb gene. Among the 375 women, 35 [9.3%] were identified as carriers of group B streptococci on the basis of the results of the cultures of specimens, compared to 42 [11.2%] on the basis of PCR assay. We found that GBS can be detected rapidly and reliably by a PCR assay in vaginal secretions from women at the time of delivery. This study also showed that the rate of incidence of GBS is high in Iranian women

Optimización de metodologías de cribaje para la búsqueda de Streptococcus agalactiae en embarazadas / Optimization of screening methodologies for the detection of Streptococcus agalactiae in pregnant women

Streptococcus agalactiae es una causa importante de morbimortalidad en mujeres embarazadas y neonatos en todo el mundo. El objetivo del presente trabajo fue determinar la utilidad del medio cromogénico chromID Strepto B de bioMérieux para detectar S. agalactiae en embarazadas cuando la muestra es sembrada directamente en dicho medio o después del enriquecimiento en caldo de Todd Hewitt selectivo, opciones que se compararon con la metodología propuesta por el CDC . Se analizaron 1924 hisopados, 962 de introito vaginal y 962 rectales, correspondientes a 962 embarazadas entre la semana 35 y 37 de gestación, asistidas en distintos hospitales. Los hisopados se sembraron directamente en el medio chromID Strepto B (CR) y luego se colocaron en un caldo de Todd Hewitt selectivo, suplementado con 15 µg/ml de ácido nalidíxico y 10 µg/ml de colistina (CTH-sel). Luego de 24 h de incubación, se realizaron subcultivos en el medio CR y en agar con 5% de sangre de carnero (ASO). La prevalencia global de S. agalactiae fue de 17,4%. La sensibilidad, la especificidad y los valores predictivos positivo y negativo del subcultivo en CR del material desarrollado en el CTH -sel fueron 98,8%, 100%, 100% y 99,7% respectivamente, con una incubación de 48 h. Los valores correspondientes de la siembra directa fueron 57,8%, 100%, 100% y 90%. La sensibilidad del subcultivo en ASO del material desarrollado en el CTH -sel fue del 85%. Se destaca el excelente rendimiento del subcultivo en CR luego del enriquecimiento en caldo de Todd Hewitt selectivo en comparación con el método propuesto por el CDC.

Streptococcus agalactiae is a significant worldwide cause of morbidity and mortality in pregnant women and their newborn infants. The objective of this work was to determine the usefulness of bioMrieux chromogenic medium chromID Strepto B (CR) for detecting S. agalactiae in pregnant women from the selective Todd-Hewitt broth (sel-THB ) against the methods proposed by the CDC . A total of 1924 swabs were analyzed, 962 from vaginal introitus and 962 rectal, belonging to 962 women in weeks 35-37 of pregnancy. The swabs were directly seeded in CR. Both swabs were later placed in sel-THB with 15 µg/ml supplement of nalidixic acid and 10 µg/ml colistin. After 24 h of incubation, subcultures in CR medium and agar containing 5% sheep blood (SBA) were performed. The prevalence found was 17.4%. Sensitivity, specificity, positive and negative predictive values of sel-THB subcultures with CR supplement and 48 h incubation were: 98.8, 100, 100 and 99.7%, respectively. The corresponding values of direct harvest of the sample were 57.8, 100, 100, and 90%, respectively. Sensitivity of sel-THB in SBA was 85%. Sel-THB subculture performance in CR was outstanding in comparison with the method proposed by the CDC.

Asymptomatic infection in family contacts of patients with human visceral leishmaniasis in Três Lagoas, Mato Grosso do Sul State, Brazil / Infecção assintomática em contactantes de pacientes com leishmaniose visceral humana em Três Lagoas, Mato Grosso do Sul, Brasil

The Brazilian city of Três Lagoas, Mato Grosso do Sul State, has experienced an urban outbreak of visceral leishmaniasis since 2000. In 2002, due to the increase in the number of cases, 46 families with cases of visceral leishmaniasis were studied to verify the prevalence of asymptomatic infection in household contacts. Indirect immunofluorescence and ELISA showed a 36.4 percent positive infection rate. There were no cases of symptomatic disease among these contacts. There was no statistically significant difference in gender or age. Median age was 21 years, and the 10-19-year age bracket was the most heavily affected (23 percent). As for family characteristics, no differences were observed in schooling or family income; most families (58.7 percent) owned their homes, which were built of masonry (97.8 percent) and had adequate infrastructure. All the families reported what were probably phlebotomine sand flies in the peridomicile. In conclusion, asymptomatic visceral leishmaniasis infection is frequent and occurs in both males and females, regardless of age.

O Município de Três Lagoas, Mato Grosso do Sul, Brasil, foi alvo de uma epidemia de leishmaniose visceral a partir de 2000. Em 2002, devido ao incremento de casos, estudou-se 46 famílias que apresentavam um caso de doença para verificar-se o percentual de positividade de infecção assintomática por leishmaniose visceral em contactantes. Encontrou-se 36,4 por cento de positividade pelos testes sorológicos Reação de Imunofluorescência Indireta e/ou imunoenzimático ELISA, sem diferença estatisticamente significativa quanto ao sexo e faixa etária. A mediana de idade foi de 21 anos, sendo a faixa etária mais acometida de 10 a 19 anos (23 por cento). Quanto às características familiares não observaram-se diferenças quanto ao nível de instrução e renda familiar; a moradia, em sua maioria, era própria (58,7 por cento), em alvenaria (97,8 por cento), com infra-estrutura adequada. Todas as famílias relataram a presença de provável flebotomíneo no peridomicílio. Conclui-se que a infecção assintomática por leishmaniose visceral é freqüente, ocorrendo em homens e mulheres, independente de faixa etária.

Prevalence of methicillin resistant Staphylococcus aureus in school children of Pokhara.

Present study was carried out to find out the prevalence of methicillin resistant Staphylococcus aureus (MRSA) in school children of Pokhara city in western, Nepal. A total of 184 randomly selected children younger than 15 years were included in the study. Nasal swabs collected were subjected to standard bacteriological culture. S. aureus isolates were identified by mannitol fermentation, coagulase positivity and DNase positivity. Antimicrobial susceptibility test was performed on muller-hinton agar (MHA) by modified Kirby-Bauer disc diffusion method. Out of total 184 nasal swabs, S. aureus was isolated in 31.0% (n=57). Among the isolates, 35.1% (n=20) were from male children whereas 64.9% (n=37) were from female. There was no significant sex difference in colonization of S. aureus. Out of 57 isolates, 56.1% (n=32) were MRSA. MRSA isolates indicated relatively high rate of resistance to antibiotic cloxacillin (68.7%) followed by ofloxacin (40.6%), tetracycline (15.6%), erythromycin (9.4%), ciprofloxacin (6.2%) and vancomycin (3.1%).This study showed a high prevalence of MRSA carriage in school children indicating the spread of MRSA in the community.

Clinical relevance of HBV DNA load in patients with chronic hepatitis B infection.

BACKGROUND: Hepatitis B virus (HBV) DNA detection and quantification are now playing an increasing role in the assessment of disease activity and response to therapy. However, viraemia levels which define various stages of HBV infection have not yet been established. AIM: To define viraemia levels which describe various stages of chronic hepatitis B virus infection. METHODS: In a retrospective study, stored sera samples of chronic hepatitis B virus (CHB) infected patients registered at AIIMS liver clinic, from January 1996 to June 2005 were subjected to competitive, quantitative PCR analysis. RESULTS: The median HBV DNA load was lowest among carriers and highest among patients with chronic hepatitis B [0 (0-8) vs. 7 (0-12) log10 copies/ml, respectively; p<0.05]. As compared to chronic hepatitis patients the DNA load was also lower among cirrhotics [7 (0-12) vs. 4.5 (0-8) log10 copies/ml, respectively; p<0.05] and hepatocellular cancer patients [ 7(0-12) vs. 0 (0-8) log10 copies/ml, respectively; p<0.05]. Patients with carriers had a DNA load which was significantly lower than e antigen negative CHB [0 (0-8) vs. 6 (0-10) log10 copies/ml; p<0.05] or e antigen positive CHB [0 (0-8) vs 8 (0-12) log10 copies/ml; p<0.05]. A threshold of 3.5 log10 copies/ml had sensitivity and specificity of 83% and 58% respectively in differentiating carriers from e antigen negative CHB. There was a strong positive correlation of HBV DNA load with inflammatory grade (R=0.334; p=0.0001), fibrosis stage (R=0.276; p=0.001) and ALT levels (R=0.378; p=0.0001). 82% (9/11) of those who lost e antigen had a decline in HBV DNA levels to <5 log10 copies/ml, whereas only 12.5% (1/8) of those who did not lose e antigen had a decline in DNA load below this level. CONCLUSIONS: HBV DNA viraemia levels correlate positively with the inflammatory grade, fibrosis stage and ALT levels. Most patients who loose e antigen have a decline in DNA load to below 5 log10 copies/ml. Further prospective studies employing repeated measurements are required to define a threshold to differentiate between HBV carriers and e antigen negative CHB.

Study on the prevalence of Pasteurella multocida carriers in slaughtered cattle and relationship with their immunity status at Ahvaz abattoir

This study was carried out on 250 slaughtered cattle at Ahvaz abattoir in Khouzestan province of Iran to investigate the occurrence of Pasteurella multocida carriers and relationship with their immunity status. Nasopharyngeal swabs and 10 ml blood samples were taken immediately after slaughter. The swabs were streaked on 5% sheep blood agar plates. Cultures were incubated at 37°C for 24h and the plates were examined for colonies resembling P. multocida. Suspicious colonies were further subcultivated and examined microscopically and biochemically. The isolates were serotyped serologically and their pathogenicity in mice was carried out. Sera samples were tested for the presence of antibody against P. multocida by indirect haemagglutination [IHA] test and sera with a titer of >/= 1:16 were considered as positive. P. multocida was isolated from the nasopharynx of 6 [2.4%] out of 247 healthy cattle examined. There was no relation between infection and sex or age. All of 6 isolates belonged to type B. They were pathogenic for mice and caused death in injected mice within less than 24h after injection. Indirect haemagglutination test revealed the titers of >/= 1:16 of P. multocida antibody in 212 [84.8%] cattle. Among 6 cattle recognized as the carriers of P. multocida, 5 were positive serologically and 2, 2 and one of them had titers 1:128, 1:64, and 1:32, respectively

Carrier detection of phenylketonuria in Iranian families by variable number tandem-repeat polymorphism analysis

This study of Iranian families assessed the usefulness of carrier detection of phenylketonuria by variable number tandem-repeat [VNTR] polymorphism analysis. We studied 171 people [45 unrelated PKU subjects, and their parents and unaffected siblings]. Of 342 chromosomes [131 non-PKU and 211 PKU], 5 VNTR alleles were identified. This VNTR system would yield a polymorphism information content of 66%, comparable to that in Europeans and higher than in Chinese. Carrier detection by segregation analysis of VNTR was informative in 89.5% of siblings. We conclude that this polymorphism is highly informative in carrier detection of PKU in the Iranian population