Epidemiological and molecular investigation of norovirus and astrovirus infections in Rio Branco, Acre, Northern Brazil: A retrospective study.

Norovirus (NoV) is a major cause of nonbacterial acute gastroenteritis (AGE) outbreaks worldwide, with infections reported in semiclosed environments, particularly in hospitals and nursing homes. Astrovirus (HAstV) is prevalent worldwide, especially in developing countries. We aimed to determine the prevalence, spatial distribution, and genetic diversity of NoV and HAstV in children under 5 years of age in Rio Branco city, Acre State, Amazon Region, Brazil. Stool samples from children with (n = 240) and without (n = 248) AGE were collected from January to December 2012 from seven neighborhoods. The overall NoV prevalence was 12.3% (60 of 488); representing 15.8% (38 of 240) of the symptomatic samples and 8.9% (22 of 248) of the controls. HAstVs infection was observed in 4.7% (23 of 488) of the samples tested, 6.2% (15 of 240) of AGE cases, and 2.4% (6 of 248) of the controls (plus two without information about feces consistency). Infections were found in all age groups with higher frequency in children less than two years of age, for both viruses. NoV was detected in all neighborhoods, with a higher concentration in the fourth (30%; 18 of 60). NoV nucleotide sequencing performed in 86.7% (52 of 60) of the positive samples showed the circulation of the strains GII.4 (57.7%; 30 of 52), GIIPe/GII.4 (19.2%; 10 of 52), GII.7, GII.Pg/GII.1, and GII.Pc (3.8%; 2 of 52 for each), GII.6 and GII.Pg (1.9%; 1 of 52 for each), and GI.3 (7.7%; 4 of 52). Three GII.4 variants were detected: Den Haag_2006b (n = 1), New Orleans_2009 (n = 1), and Sydney_2012 (n = 14). HAstV types HAstV-1a (81.8%; 9 of 11) and HAstV-2c (18.2%; 2 of 11) were observed in the 47.8% (11 of 23) of characterized samples. This is the first data obtained in Acre State regarding the prevalence of these viruses and provides epidemiological and molecular information for a better understanding of their role among children with and without AGE.

Population and genetic study of Vibrio cholerae from the amazon environment confirms that the WASA-1 prophage is the main marker of the epidemic strain that circulated in the region.

Vibrio cholerae is a natural inhabitant of many aquatic environments in the world. Biotypes harboring similar virulence-related gene clusters are the causative agents of epidemic cholera, but the majority of strains are harmless to humans. Since 1971, environmental surveillance for potentially pathogenic V. cholerae has resulted in the isolation of many strains from the Brazilian Amazon aquatic ecosystem. Most of these strains are from the non-O1/non-O139 serogroups (NAGs), but toxigenic O1 strains were isolated during the Latin America cholera epidemic in the region (1991-1996). A collection of environmental V. cholerae strains from the Brazilian Amazon belonging to pre-epidemic (1977-1990), epidemic (1991-1996), and post-epidemic (1996-2007) periods in the region, was analyzed. The presence of genes related to virulence within the species and the genetic relationship among the strains were studied. These variables and the information available concerning the strains were used to build a Bayesian multivariate dependency model to distinguish the importance of each variable in determining the others. Some genes related to the epidemic strains were found in environmental NAGs during and after the epidemic. Significant diversity among the virulence-related gene content was observed among O1 strains isolated from the environment during the epidemic period, but not from clinical isolates, which were analyzed as controls. Despite this diversity, these strains exhibited similar PFGE profiles. PFGE profiles were significant while separating potentially epidemic clones from indigenous strains. No significant correlation with isolation source, place or period was observed. The presence of the WASA-1 prophage significantly correlated with serogroups, PFGE profiles, and the presence of virulence-related genes. This study provides a broad characterization of the environmental V. cholerae population from the Amazon, and also highlights the importance of identifying precisely defined genetic markers such as the WASA-1 prophage for the surveillance of cholera.

Frequency of Shigella flexneri serotypes isolated in the state of Pará, Brazil (1979-2009) / Frequência de sorotipos de Shigella flexneri isoladas no estado do Pará, Brasil (1979-2009)

O gênero Shigella tem sido uma das causas mais comuns de diarréia em países pouco desenvolvidos, sendo responsável pela mortalidade e / ou morbidade em população de alto risco, como crianças menores de cinco anos e idosos. Este estudo, realizado no Instituto Evandro Chagas (IEC) , Estadodo Pará, Brasil, no período de 1979 a 2009, teve como objetivo avaliar a frequência de espécies e sorotipos de 122 isolados de Shigella spp. provenientes de pacientes com diarréia aguda. Os isolados bacterianos foram identificados por meios de culturas seletivos e indicadores e testes bioquímicos. Todos os isolados foram identificados quanto ao sorogrupo e sorotipo por meio da soroaglutinaçãoem lâmina. Os sorogrupos mais frequentemente encontrados foram S. flexneri (66,4por cento) e S. sonnei(32,8por cento). O sorotipo de S. flexneri mais frequente foi o 2a (54,3por cento) seguido de 1b (17,2por cento). A maioria dos pacientes tinham idade entre 0 a 5 anos (44,6por cento), dos quais 38,2por cento apresentaram S. flexneri e 47,5por cento S. sonnei. Pacientes com idade superior a 18 anos representaram 39,2por cento das infecções, sendo 37,0por cento casos de S. flexneri, 32,5por cento de S. sonnei e um isolado de S. boydii. Esses resultados reforçam a necessidade de uma vigilância epidemiológica contínua no Estado do Pará.

Genome-wide study of the defective sucrose fermenter strain of Vibrio cholerae from the Latin American cholera epidemic.

The 7th cholera pandemic reached Latin America in 1991, spreading from Peru to virtually all Latin American countries. During the late epidemic period, a strain that failed to ferment sucrose dominated cholera outbreaks in the Northern Brazilian Amazon region. In order to understand the genomic characteristics and the determinants of this altered sucrose fermenting phenotype, the genome of the strain IEC224 was sequenced. This paper reports a broad genomic study of this strain, showing its correlation with the major epidemic lineage. The potentially mobile genomic regions are shown to possess GC content deviation, and harbor the main V. cholera virulence genes. A novel bioinformatic approach was applied in order to identify the putative functions of hypothetical proteins, and was compared with the automatic annotation by RAST. The genome of a large bacteriophage was found to be integrated to the IEC224's alanine aminopeptidase gene. The presence of this phage is shown to be a common characteristic of the El Tor strains from the Latin American epidemic, as well as its putative ancestor from Angola. The defective sucrose fermenting phenotype is shown to be due to a single nucleotide insertion in the V. cholerae sucrose-specific transportation gene. This frame-shift mutation truncated a membrane protein, altering its structural pore-like conformation. Further, the identification of a common bacteriophage reinforces both the monophyletic and African-Origin hypotheses for the main causative agent of the 1991 Latin America cholera epidemics.

Complete genome sequence of a sucrose-nonfermenting epidemic strain of Vibrio cholerae O1 from Brazil.

We report the genome sequence of Vibrio cholerae strain IEC224, which fails to ferment sucrose. It was isolated from a cholera outbreak in the Amazon. The defective sucrose phenotype was determined to be due to a frameshift mutation, and a molecular marker of the Latin American main epidemic lineage was identified.

Antimicrobial Resistance of Shigella spp. isolated in the State of Pará, Brazil / Resistência Antimicrobiana de Shigella spp. isoladas no Estado do Pará

INTRODUCTION: Shigella spp. are Gram-negative, nonsporulating, rod-shaped bacteria that belong to the family Enterobacteriaceae and are responsible for shigellosis or bacillary dysentery, an important cause of worldwide morbidity and mortality. METHODS: We studied the antibiotic resistance profiles of 122 Shigella spp. strains (81 S. flexneri, 41 S. sonnei, 1 S. boydii) isolated from patients (female and male from 0 to 80 years of age) presenting diarrhea in different districts of the State of Pará, in the North of Brazil. The antibiotic resistance of the strains, isolated from human fecal samples, was determined by the diffusion disk method and by using the VITEK-2 system. RESULTS: The highest resistance rate found was the resistance rate to tetracycline (93.8 percent), followed by the resistance rate to chloramphenicol (63.9 percent) and to trimethoprim/sulfamethoxazole (63.1 percent). Resistance to at least three drugs was more common among S. flexneri than S. sonnei (39.5 percent vs. 10 percent). Six (4.9 percent) strains were susceptible to all the antibiotics tested. All strains were susceptible to cefotaxime, ceftazidime, ciprofloxacin, nalidixic acid and nitrofurantoin. CONCLUSIONS: High rates of multidrug resistance in Shigella spp. are a serious public health concern in Brazil. It is extremely important to continuously monitor the antimicrobial resistances of Shigella spp. for effective therapy and control measures against shigellosis.

INTRODUÇÃO: Shigella spp. são bactérias Gram-negativas, não esporuladas, em forma de bastonete, pertencentes a família Enterobacteriaceae responsáveis pela shigelose ou disenteria bacilar, uma importante causa de mortalidade e morbidade mundial. MÉTODOS: Foi estudado o perfil de resistência a antimicrobianos de 122 amostras de Shigella spp. (81 S. flexneri, 41 sonnei, 1 S. boydii) isoladas de pacientes (sexo feminino e masculino com faixa etária de 0 a 80 anos) com distúrbios gastrointestinais em diferentes municípios no Estado do Pará, Brasil. A resistência antimicrobiana das amostras isoladas de coprocultura, foi determinada pelo método de difusão em disco e pelo sistema Vitek II. RESULTADOS: A maior resistência foi observada em relação à tetraciclina (93,8 por cento), seguida de cloranfenicol (63,9 por cento), e trimetoprimsulfametoxazol (63,1 por cento). Multirresistência a pelo menos três antimicrobianos foi mais comum em S. flexneri comparada a S. sonnei (39,5 por cento vs. 10 por cento). Seis (4,9 por cento) amostras foram sensíveis a todos antimicrobianos testados. Todas as amostras apresentaram sensibilidade a cefotaxima, ceftazidima, ciprofloxacina, ácido nalidixico e nitrofurantoína. CONCLUSÕES: As altas taxas de multirresistência de Shigella spp. são um sério problema de saúde pública no Brasil. Sendo assim, torna-se extremamente importante um monitoramento contínuo da resistência antimicrobiana de Shigella spp. para uma terapia efetiva e medidas de controle contra shigelose.

Antimicrobial resistance of Shigella spp. isolated in the State of Pará, Brazil.

INTRODUCTION: Shigella spp. are Gram-negative, nonsporulating, rod-shaped bacteria that belong to the family Enterobacteriaceae and are responsible for shigellosis or bacillary dysentery, an important cause of worldwide morbidity and mortality. METHODS: We studied the antibiotic resistance profiles of 122 Shigella spp. strains (81 S. flexneri, 41 S. sonnei, 1 S. boydii) isolated from patients (female and male from 0 to 80 years of age) presenting diarrhea in different districts of the State of Pará, in the North of Brazil. The antibiotic resistance of the strains, isolated from human fecal samples, was determined by the diffusion disk method and by using the VITEK-2 system. RESULTS: The highest resistance rate found was the resistance rate to tetracycline (93.8%), followed by the resistance rate to chloramphenicol (63.9%) and to trimethoprim/sulfamethoxazole (63.1%). Resistance to at least three drugs was more common among S. flexneri than S. sonnei (39.5% vs. 10%). Six (4.9%) strains were susceptible to all the antibiotics tested. All strains were susceptible to cefotaxime, ceftazidime, ciprofloxacin, nalidixic acid and nitrofurantoin. CONCLUSIONS: High rates of multidrug resistance in Shigella spp. are a serious public health concern in Brazil. It is extremely important to continuously monitor the antimicrobial resistances of Shigella spp. for effective therapy and control measures against shigellosis.

Outbreak of neonatal infection by an endemic clone of Serratia marcescens.

INTRODUCTION: The outbreak occurred between February and June 2006 and included identification of the cases, analysis of medical records, cultures from environmental sources, resistance analyses and genotyping profile of Serratia marcescens. METHODS: The cultures were composed of 13 blood isolates, 17 rectal and hand swabs and air sampling. RESULTS: The data obtained by pulsed-field gel electrophoresis exhibited three strains that contaminated 24 patients. Systemic infection was the most common in neonates with lower weight, long periods of hospitalization, premature delivery and the use of mechanical ventilation. CONCLUSIONS: This investigation revealed the multifactorial nature of the outbreak. An endemic clone of S. marcescens was detected.

Outbreak of neonatal infection by an endemic clone of Serratia marcescens / Surto de infecção neonatal a partir de clone endêmico de Serratia marcescens

INTRODUCTION: The outbreak occurred between February and June 2006 and included identification of the cases, analysis of medical records, cultures from environmental sources, resistance analyses and genotyping profile of Serratia marcescens. METHODS: The cultures were composed of 13 blood isolates, 17 rectal and hand swabs and air sampling. RESULTS: The data obtained by pulsed-field gel electrophoresis exhibited three strains that contaminated 24 patients. Systemic infection was the most common in neonates with lower weight, long periods of hospitalization, premature delivery and the use of mechanical ventilation. CONCLUSIONS: This investigation revealed the multifactorial nature of the outbreak. An endemic clone of S. marcescens was detected.

INTRODUÇÃO: O surto ocorreu entre fevereiro a junho de 2006 e incluiu identificação de casos, análise dos prontuários, culturas ambientais, análise de resistência e genotipagem dos isolados de Serratia marcescens. MÉTODOS: Os cultivos foram compostos de 13 isolados de sangue e 17 swabs de reto e mãos e amostras do ar. RESULTADOS: Os dados obtidos por eletroforese de campo pulsado evidenciaram três cepas que contaminaram 24 pacientes. Infecção sistêmica foi mais comum em neonatos com menor peso, longo tempo de internação, nascimento prematuro e uso de respiração mecânica. CONCLUSÕES: Foi evidenciada a natureza multifatorial do surto. Foi encontrado um clone endêmico de S. marcescens.

Occurrence and composition of class 1 and class 2 integrons in clinical and environmental O1 and non-O1/non-O139 Vibrio cholerae strains from the Brazilian Amazon.

This study identified and characterised class 1 and 2 integrons in clinical and environmental Vibrio cholerae O1 and non-O1/non-O139 strains isolated from the Brazilian Amazon. The aadA2 and aadA7 gene cassettes were found in class 1 integrons in two genotypes of environmental V. cholerae non-O1/non-O139. Empty integrons were found in strains from the Brazilian cholera epidemic. A class 2 integron was detected in one strain from the V. cholerae Amazonia lineage harbouring sat1 and aadA1 genes. All isolates were resistant to aminoglycosides, indicating aadA functionality. These findings suggest that environmental bacteria act as cassette reservoirs that favour the emergence of resistant pathogens.

Occurrence and composition of class 1 and class 2 integrons in clinical and environmental O1 and non-O1/non-O139 Vibrio cholerae strains from the Brazilian Amazon

This study identified and characterised class 1 and 2 integrons in clinical and environmental Vibrio cholerae O1 and non-O1/non-O139 strains isolated from the Brazilian Amazon. The aadA2 and aadA7 gene cassettes were found in class 1 integrons in two genotypes of environmental V. cholerae non-O1/non-O139. Empty integrons were found in strains from the Brazilian cholera epidemic. A class 2 integron was detected in one strain from the V. cholerae Amazonia lineage harbouring sat1 and aadA1 genes. All isolates were resistant to aminoglycosides, indicating aadA functionality. These findings suggest that environmental bacteria act as cassette reservoirs that favour the emergence of resistant pathogens.

Detecção de bactérias enteropatogênicas e enteroparasitas em pacientes com diarreia aguda em Juruti, Pará, Brasil / Detection of enteropathogenic bacteria and enteroparasites in patients with acute diarrhea in Juruti, Pará, Brazil

Com o intuito de determinar a frequência de bactérias enteropatogênicas e enteroparasitas em pacientes com diarreia aguda no Município de Juruti, Pará, o qual passa por intenso processo imigratório face o grande projeto de exploração mineral, avaliaram-se 263 casos de diarreia aguda, dos quais 19 por cento foram atribuídos a bactérias enteropatogênicas, destacando-se a Shigella spp, que representou 13,7 por cento. Salmonella spp, Aeromonas spp e Plesiomonas shigelloides também foram detectados. Os sorotipos de Shigella mais frequentemente encontrados foram S. flexneri (61,1 por cento) e S. sonnei (38,9 por cento). Entre as Salmonella, identificaram-se os seguintes sorotipos: S. Panama (2), S. Newport (2), S. Bredeney, S. Saintpaul e S. Gaminara. A infecção pelos protozoários alcançou 85,3 por cento tendo como principais responsáveis, por ordem de frequência, Blastocystis hominis (37,3 por cento), Entamoeba histolytica/E. dispar (22,8 por cento), Endolimax nana (16,7 por cento), Entamoeba coli (9,5 por cento) e Giardia lamblia (8,4 por cento). Esses resultados fornecem valiosos subsídios à vigilância epidemiológica e ambiental, demonstrando as condições insatisfatórias de saneamento básico em que vive a população do Município.

With the aim of determining the frequency rate of enteropathogenic bacteria and enteroparasites in patients with acute diarrhea in the Municipality of Juruti, Pará State, which has been facing an intense migratory process due to a great mining project, we analyzed 263 cases of acute diarrhea. A total of 19 percent of those cases were related to enteropathogenic bacteria, particularly Shigella spp. that accounted for 13.7 percent of the cases. Salmonella spp, Aeromonas spp and Plesiomonas shigeloide were also detected. The most frequent Shigella serotypes found were S. flexneri (61.1 percent) and S. sonnei (38.9 percent). Among the Salmonella, we could observe the following serotypes: S. Panama (2), S. Newport (2), S. Bredeney, S. Saintpaul and S. Gaminara. The infection caused by protozoa reached 85.3 percent, mostly due to Blastocystis hominis (37.3 percent), Entamoeba histolytica/E. dispar (22.8 percent), Endolimax nana (16.7 percent), Entamoeba coli (9.5 percent) and Giardia lamblia (8.4 percent). These results provide valuable data to epidemiological and environmental surveillance because it presents the unsatisfactory basic sanitary conditions of the local population.

Bactérias isoladas de culicídeos (Diptera: Nematocera) hematófagos em Belém, Pará, Brasil / Isolated bacteria from hematophagous Culicidae (Diptera: Nematocera) in Belém, Pará State, Brazil

As bactérias estão abundantemente distribuídas na natureza, participam da microbiota humana e animal, e algumas causam doenças. Têm a sua distribuição ampliada quando são veiculadas por algum vetor. Os dípteros da família Culicidae são vetores em epidemias de grande interesse para a saúde pública; no entanto, a associação entre bactérias e culicídeos foi pouco abordada. Para avançar conhecimento sobre esta temática, foi proposto isolar e identificar bactérias que estão sendo transportadas em culicídeos hematófagos em Belém, Pará. As coletas dos culicídeos foram realizadas com armadilha luminosa do tipo CDC, em oito pontos de coleta da área metropolitana de Belém, que apresentam características ambientais distintas. Foram coletados 296 exemplares de culicídeos, sendo que nove foram identificados até o nível de espécie e quatro até o subgênero. Destas amostras foi possível identificar 17 espécies de bactérias, outras sete somente foram identificadas até o gênero. Culex quinquefasciatus e Anopholes aquasalis foram os mais abundantes entre os culicídeos. As espécies de bactérias Gemella haemolysans e Enterobacter cloacae foram as mais abundantes nas amostras. Os pontos de coleta localizados nos bairros da Terra Firme e Curió Utinga foram os que apresentaram maior diversidade de espécies de culicídeos.

Bacteria are largely distributed in nature, especially when carried by a vector. They comprise large portions of the human and animal microbiota, and some cause diseases. The diptera of the family Culicidae are directly involved in the vectoring of epidemics of great interest for public health. However, the association between bacteria and Culicidae has been scarcely studied. In order to deepen the knowledge on this subject, we isolated and identified bacteria which have been transported in hematophagous Culicidae in the City of Belém, Pará State. The collection of 296 mosquitoes was carried out using a CDC light trap in eight collection localities, which presented different environmental characteristics within the metropolitan area of Belém. Some were identified to the species level (9) and others to the subgenus (4). It was possible to identify 17 species of bacteria; seven bacteria could only be identified up to their genus. Culex quinquefasciatus and Anopheles aquasalis were the most frequent Culicidae. The most frequent species of bacteria found in the samples were Gemella haemolysans and Enterobacter cloacae. The collection localities in the Terra-firme and Curió-utinga districts presented the largest diversity of species of Culicidae.

Sorovares de Salmonella de origem humana identificados no Estado do Pará, Brasil, no período de 1991 a 2008 / Salmonella serovars of human origin identified in Pará State, Brazil from 1991 to 2008

A salmonelose é de distribuição cosmopolita, acometendo todas as faixas etárias, tanto nos países desenvolvidos, como naqueles em desenvolvimento. Este estudo tem como objetivo identificar os sorovares de Salmonella isolados de casos deinfecção humana ocorridos em 43 municípios do Estado do Pará no período de 1991 a 2008. Foram utilizadas 890 amostras de Salmonella em coproculturas e hemoculturas, aí incluídos 55 isolamentos de S. Typhi nas fezes e sangue, simultaneamente, de indivíduos sintomáticos. Os casos de infecção por Salmonella foram distribuídos em 13 sorogrupos,com destaque para o grupo O:9 (68,1 por cento). Foram identificados 47 sorovares de Salmonella, destacando-se S. Typhi (58,9 por cento), S. Enteritidis (5,4 por cento) e S. Saintpaul (2,5 por cento). Ressalta-se a maior prevalência de S. Typhi (58,9 por cento) dentre os 47 sorovares identificados, o que demonstra que a febre tifóide representa um sério problema de saúde pública na Região Norte do País, e que necessita de maior atenção dos serviços de saúde quanto à vigilância epidemiológica e ambiental,assim como medidas efetivas para a prevenção e controle.

Salmonellosis presents a cosmopolitan distribution and affects all age groups, not only in developed countries, but also in developing ones. This study aimed to identify the serovars of Salmonella isolated from human infections occurring in 43 areas of Pará State from 1991 to 2008. Eight hundred and ninety samples of Salmonella isolated in coprocultures and blood cultures were analyzed, including 55 isolations of S. Typhi from feces and blood of symptomatic individuals, simultaneously. The cases of Salmonella infections were distributed into 13 serogroups. The majority of them were in group O:9 (68.1 percent), and 47 serovars of Salmonella were identified, including S. Typhi (58.9 percent), S. Enteritidis (5.4 percent) and S. Saintpaul (2.5 percent). S. Typhi was the most prevalent (58.9 percent) among the 47 identified serovars, which demonstrates that typhoid fever is a serious public health problem in northern Brazil and requires increased attention from health agencies regarding epidemiological and environmental surveillance as effective measures for its prevention and control.

Morbimortalidade por gastroenterites no Estado do Pará / Morbidity and mortality caused by gastroenteritis in Pará State, Brazil

No Brasil, as gastroenterites acometem principalmente as crianças menores de 5 anos de idade e são consideradas um importante problema de saúde pública. O declínio da morbimortalidade por enteroinfecções resulta na queda da mortalidade infantil e da mortalidade por doenças infecciosas nos países em desenvolvimento. O presente trabalho é um estudo descritivo, realizado em colaboração com o Departamento de Epidemiologia do Estado do Pará, desenvolvido com intuito de conhecer a importância das gastroenterites como causa de internações e óbitos no Estado do Pará. Realizou-se: o levantamento de dados sobre mortalidade e internação por meio dos Sistemas de Informação em Saúde edo Monitoramento das Doenças Diarreicas Agudas durante o período de 2000 a 2004; além dos cálculos dos indicadores de saúde. No cômputo geral, foram notificados 590.595 casos de diarreia. Foi observado um aumento no número de casos de diarreia notificados no Monitoramento das Doenças Diarreicas Agudas durante este período, sendo as maiores frequências encontradas na faixa etária de 1 a 4 anos de idade (média de 48.887 casos), seguido de 33.151 casos em menores de 1 ano de idade. A taxa de internação por diarreia em menores de 1 ano de idade foi de 35 por mil nascidos vivos em 2004. No período estudado, o coeficiente de mortalidade diminuiu, atingindo em 2004 o valor de 2,91 paracada 100 mil habitantes, seguindo a tendência de diminuição das taxas de mortalidade por diarreia no Brasil. Mesmo com este declínio, a diarreia ainda se apresenta como uma das principais causas de morbimortalidade no Estado do Pará, acometendo especialmente crianças menores de 1 ano de idade.

In Brazil, gastroenteritis mainly affects children aged 0 to 5 years and is considered a significant public health problem.The reduction of the morbidity and mortality rates caused by gastroenteritis is responsible for the decrease in the rates of overall infant mortality and infant mortality due to infectious diseases in developing countries. This work is a descriptive study developed in collaboration with the Epidemiology Department of Pará State in order to determine the importance of gastroenteritis as a cause of hospitalizations and deaths in Pará State. Initially, data about morbidity and hospitalization were obtained from Information Systems on mortality, health and hospital admissions and from health indicators and the Monitoring of Acute Diarrheal Diseases (MADD) program in the period between 2000 and 2004.There were 590,595 recorded cases of diarrhea. There was an increase in the number of cases of diarrhea notified by MADD during this period, with the highest frequency rates found in children aged 1 to 4 years old (average of 48,887 cases), followed by 33,151 cases in children below 1 year of age. In 2004, the hospitalization rate due to diarrhea in children below one was of 35 per 1 thousand live births. The coefficient of mortality decreased during the period studied, reaching 2.91 per 100 thousand inhabitants in 2004, following the reduction trend of mortality rates by diarrhea in Brazil. Despite this reduction, diarrhea remains a major cause of morbidity and mortality in Pará State, especially affecting children below 1 year of age.

Desenvolvimento de PCR multiplex para detecção e diferenciação de categorias de Escherichia coli diarreiogênicas / Development of multiplex PCR to detect and differentiate the categories of diarrheagenic Escherichia coli

INTRODUÇÃO: As Escherichia coli diarreiogênicas (DEC) são consideradas importante causa de diarréia nos países em desenvolvimento. Para sua correta identificação, esses microrganismos devem ser diferenciados dos membros não patogênicos da microbiota intestinal. As DEC podem ser classificadas em seis categorias, de acordo com seu mecanismo de patogenicidade. MATERIAIS E MÉTODOS: Foram desenvolvidos e avaliados dois sistemas de PCR multiplex para a detecção de E. coli enteropatogênicas (EPEC), enterotoxigênica (ETEC), enteroinvasora (EIEC) e produtora da toxina de Shiga (STEC). RESULTADOS: Quatro categorias diarreiogênicas foram detectadas entre os isolados de E. coli obtidos de indivíduos infectados pelo HIV, com EIEC e EPEC representando os patótipos mais frequentes. Duas STEC stx1 e eae positivas foram identificadas, sendo este o primeiro relato de isolamento dessa categoria em indivíduos infectados pelo HIV no estado do Pará. A PCR multiplex mostrou-se como técnica eficiente, rápida e reprodutível para detecção dos isolados de DEC. Os dois sistemas de PCR multiplex apresentaram resultados 100 por cento concordantes com os encontrados na PCR simples. CONCLUSÃO: Devido sua simplicidade, economia e eficiência torna-se possível a aplicação dos protocolos multiplex para agilizar o diagnóstico molecular das categorias de DEC, o que promoverá a elaboração de novos projetos de pesquisa e darão suporte as atividades de vigilância epidemiológica desenvolvidos pelos institutos de saúde pública...

INTRODUCTION: Diarrheagenic Escherichia coli (DEC) are considered an important cause of diarrhea in developing countries. The correct identification of these microorganisms depends on their differentiation from non-pathogenic members of the intestinal microbiota. DEC can be classified into one of six categories according to their mechanism of pathogenicity. MATERIALS AND METHODS: Two multiplex PCR systems used to detect enteropathogenic (EPEC), enterotoxigenic (ETEC), enteroinvasive (EIEC) and Shiga Toxin-producing (STEC) E. coli were evaluated and described. RESULTS: Four categories of DEC were detected among isolates of E. coli obtained from individuals infected with HIV. EIEC and EPEC were among the most prevalent pathotypes. Furthermore, two STEC strains that were both stx1-and eae-positive were identified. This is the first report of this kind of isolation in individuals infected with HIV in the State of Pará. Multiplex PCR proved to be an efficient, fast and reproducible technique for detection of DEC isolates. Both multiplex PCR systems described here produced results 100 per cent similar to those obtained from individual PCR reactions. CONCLUSION: Given their simplicity, cost and efficiency, it is possible to use these protocols to expedite the molecular diagnosis of the distinct categories of DEC. In addition to facilitating the development of new research projects, these findings could support the epidemiological surveillance undertaken by public health agencies and institutes...

Caracterização da resistência antimicrobiana de amostras de Shigella spp. isoladas em Belém, Estado do Pará, Brasil (1990-2000) / Characterization of antimicrobial resistance of samples of Shigella spp. isolated in Belém, Pará State, Brazil (1990-2000)

Avaliou-se a resistência antimicrobiana de amostras de Shigella spp. isoladas de membros da população com faixa etárias de 6 meses a 81 anos, habitantes da Cidade de Belém, Estado do Pará, no período de 1990 a 2000. Foram analisadas 50 amostras de Shigella spp. identificadas no Laboratório de Enteroinfecções Bacterianas da Seção de Bacteriologia e Micologia do Instituto Evandro Chagas e mantidas na bacterioteca da referida seção. Na caracterização fenotípica, 32 (64 por cento) dos isolados foram identificados como S. flexneri e 18 (36 por cento) como S. sonnei. Resistência a cefalotina, cefazolina, cefuroxima, cefuroxima axetil e tobramicina foi observada em 100 por cento das amostras, embora as mesmas apresentassem 100 por cento de sensibilidade a cefpodoxima, ceftriaxona, levofloxacina e norfloxacina. Das amostras, 2 por cento apresentaram resistência a ticarcilina/ácido clavulânico, 8 por cento a cefoxitina e 44 por cento a ticarcilina. Os resultados obtidos evidenciaram a acentuada resistência a diversos antimicrobianos desta enterobactéria causadora de graves infecções em humanos.

We evaluated the antimicrobial resistance of Shigella spp samples. isolated from members of the population aged from 6 months to 81 years, inhabitants of the City of Belem, Pará, from 1990 to 2000. We analyzed 50 samples of Shigella spp. identified in the laboratory of bacterial intestinal infections of Bacteriology and Mycology Section of the Instituto Evandro Chagas and held in bacterioteca of that section. Phenotypic characterization, 32 (64 per cent) isolates were identified as S. flexneri and 18 (36 por cent) as S. sonnei. Resistance to cephalothin, cefazolin, cefuroxime, cefuroxime axetil and tobramycin was observed in 100 per cent of the samples, although they present 100 per cent susceptibility to cefpodoxime, ceftriaxone, levofloxacin and norfloxacin. From the samples, 2 per cent were resistant to ticarcillin / clavulanic acid, 8 per cent to 44 per cent to cefoxitin and ticarcillin. The results showed a marked resistance to various antibiotics of enterobacteria causing serious infections in humans.

Vigilância ambiental para cólera na região metropolitana de Bélem, Pará, no período de 1999 a 2006 / Environmental surveillance of cholera in the metropolitan region of Belém, Pará, Brazil, 1999-2006

Como parte do programa de vigilância ambiental para cólera em Belém, foi analisado, entre os anos de 1999 a 2006, um total de 704 amostras de águas superficiais e efluentes de esgoto, e, destas, 34,8 por cento foram positivas para V. cholerae e 11,8 por cento o foram para V. mimicus. Não foi isolada nenhuma amostra de V. cholerae O1 ou O139 durante este período. Os resultados do estudo demonstraram que o V. cholerae sorogrupo O1 não está circulando nos ambientes avaliados em sua forma viável e cultivável pelos métodos convencionais de cultura, entretanto, sabe-se que o mesmo é capaz de se manter em ambientes aquáticos com características semelhantes às encontradas na região amazônica por períodos suficientes para sua disseminação. Sugere-se a manutenção da vigilância ativa para cólera, a inclusão de novas metodologias buscando o conhecimento acerca da ocorrência ambiental de Vibrio cholerae O1 na sua forma viável, porém não cultivável, e a pesquisa de fatores de virulência nos isolados já obtidos.

[Nested-PCR for gene that encodes the antigen b applied to the diagnosis of pulmonary tuberculosis]. / Nested-PCR do gene que codifica o antígeno b aplicada ao diagnóstico da tuberculose pulmonar.

The polymerase chain reaction used for amplifying an internal sequence of a previously amplified fragment (nested-PCR) was investigated as a complementary alternative for searching for alcohol-acid resistant bacilli and Mycobacterium tuberculosis cultures in Lowenstein-Jensen medium. 144 sputum samples were investigated from patients with suspected tuberculosis that were sent to the Tuberculosis Laboratory of the Evandro Chagas Institute in Belém, between June 2002 and December 2003. From the 144 samples, 121 were characterized as tuberculosis: 119 were positive in cultures, 95 under bacilloscopy and 128 using nested-PCR. The sensibility of the nested-PCR was 96% (116/121), while the specificity was 48% (11/23). Nested-PCR may be a complementary tool for diagnosing tuberculosis, since it presents sensitivity equivalent to that of cultures. However, further evaluations are needed with the aim of minimizing the number of false-positive results.

Nested-PCR do gene que codifica o antígeno b aplicada ao diagnóstico da tuberculose pulmonar / Nested-PCR for gene that encodes the antigen b applied to the diagnosis of pulmonary tuberculosis

A reação em cadeia da polimerase usada para amplificação de uma seqüência interna de um fragmento previamente amplificado (nested-PCR) foi investigada como uma alternativa complementar a pesquisa de bacilos álcool ácido resistentes e a cultura do Mycobacterium tuberculosis em meio de Lowenstein-Jensen. Foram investigadas 144 amostras de escarro de pacientes suspeitos de tuberculose encaminhados ao Laboratório de Tuberculose do Instituto Evandro Chagas em Belém, no período de junho de 2002 a dezembro de 2003. Das 144 amostras, 121 foram caracterizadas como tuberculose, 119 foram positivas na cultura, 95 na baciloscopia e 128 na nested-PCR. A sensibilidade da nested-PCR foi 96 por cento (116/121), enquanto a especificidade foi 48 por cento (11/23). A nested-PCR poderá ser uma ferramenta complementar para o diagnóstico da tuberculose, pois apresenta sensibilidade equivalente à cultura, no entanto, necessita de maiores avaliações visando minimizar o número de resultados falso-positivos.

The polymerase chain reaction used for amplifying an internal sequence of a previously amplified fragment (nested-PCR) was investigated as a complementary alternative for searching for alcohol-acid resistant bacilli and Mycobacterium tuberculosis cultures in Lowenstein-Jensen medium. 144 sputum samples were investigated from patients with suspected tuberculosis that were sent to the Tuberculosis Laboratory of the Evandro Chagas Institute in Belém, between June 2002 and December 2003. From the 144 samples, 121 were characterized as tuberculosis: 119 were positive in cultures, 95 under bacilloscopy and 128 using nested-PCR. The sensibility of the nested-PCR was 96 percent (116/121), while the specificity was 48 percent (11/23). Nested-PCR may be a complementary tool for diagnosing tuberculosis, since it presents sensitivity equivalent to that of cultures. However, further evaluations are needed with the aim of minimizing the number of false-positive results.