Rotavirus excretion in naturally infected pigs with and without diarrhoea.

Seven hundred and fifty faecal samples from piglets ranging from 1 to 60 days old were studied for the presence of group A rotavirus by polyacrylamide gel electrophoresis (PAGE) and by enzyme immunoassay (EIA). From 451 diarrhoeic pigs, 117 (25.94%) were positive for rotavirus and only 45 (15.05%) of 299 pigs without diarrhoea excreted the virus (P < 0.005). When these animals were separated into four age groups with regard to the presence or absence of diarrhoea, it was observed that the excretion of rotavirus was associated with diarrhoea in piglets, both before and after weaning.

Genotyping of group A rotavirus samples from Brazilian children by probe hybridization.

The G genotyping of 74 group A rotavirus samples was done by RNA-DNA hybridization (dot-blot) using oligonucleotide probes for the VP7 gene region of the human rotavirus serotypes/genotypes 1, 2, 3 and 4. Thirty-one samples could be genotyped by dot-blot showing the following results: G1 = 16, G4 = 6, G3 = 5, and G2 = 4. The data show circulation of genotypes G1-G4 and the predominance of G1. The knowledge of genotypes provides important information concerning rotavirus circulation in Central Brazil.

Rotavirus identification in jejunal juice and stools of acute and chronic forms of infantile gastroenteritis.

1. The present study investigates, by means of a combined enzyme immunoassay for rotaviruses and adenoviruses (EIARA), the occurrence of rotaviruses in stools and jejunal juices from 31 children with acute diarrhea and 18 with chronic diarrhea. 2. Stools from 8 acute cases contained rotaviruses (26%). In two of these cases rotaviruses were also detected in the jejunal juice. 3. In the chronic diarrhea group we identified rotaviruses in the stools of one patient and in the jejunal juice of another. 4. Some of the electropherotypes of the rotaviruses identified showed different patterns of RNA migration. 5. Abnormalities of the jejunal mucosa were characterized in 6 acute rotavirus-positive cases. No morphological or functional abnormalities of the intestinal mucosa were observed in the chronic diarrhea rotavirus-positive cases.

Serotypes and subgroups of rotavirus isolated from children in central Brazil.

Group A rotavirus, obtained from children of Goiânia, Brazil, during 1987-1994, were analyzed for subgroup and G serotype by enzyme-linked immunosorbent assay with monoclonal antibodies. The index of serotyping obtained was 61.4% with the following proportions: G1--19.7%, G2--28.0%, G3--9.8%, G4--1.5%, and G5--2.3%. It was observed that G1 occurred from 1987 to 1989 and from 1993 to 1994, and G2 from 1990 to 1993. About 94% of the samples (85/90) could be subgrouped with the following results: 55.5% for SG II, 7.8% SG I, and 31.1% for SG non-I-non-II. Unusual relationship patterns were also detected among serotypes, subgroups, and profiles of electropherotypes in 57.0% of the samples: 20 of them were G2/SG II/"long" profile. The results suggest that variation in temporal and regional characteristics should be considered in the development of rotavirus vaccine.

Diarrheal diseases in Brazil: clinical features of rotavirus-associated gastroenteritis in children.

This study was undertaken to detect the presence of rotavirus in the stools of children with gastroenteritis, using the enzyme-linked-immunosorbent assay (ELISA), and to compare the signs and symptoms of rotavirus-positive and -negative children. Over a period of fifteen months, 367 children ranging in age from less than 1 month to 5 years or more with diarrhea and 86 children, in the same age group, without diarrhea and respiratory infections, used as controls, were evaluated. Human rotavirus was detected in 15.8% of children with diarrhea attending out-patient clinics and in 28.9% of patients seen by general practitioners. In the control groups, the percentages of identification of rotavirus were 1.4% and 5.5% respectively. Frequency of other enteropathogens was determined. The hydration state of diarrheal cases, different clinical symptoms and the type of medical attendance distinguished the rotavirus positive from the rotavirus negative patients.

Relative prevalence of rotavirus diarrhoea in children attending outpatient departments of hospitals and general practitioners in Sao Paulo, Brazil.

The study was done to know the relative prevalence of rotavirus diarrhoea in 329 children with diarrhoea aged less than 1 month to 6 years (32 were of unknown age) attending the outpatient departments (OPD) of public hospitals and 38 comparable patients treated by general practitioners (GP) in Sao Paulo, Brazil. Forty-three age-matched patients without any diarrhoea or respiratory symptoms, 28 from the hospital OPDs and 15 from the GPs, served as controls. Rotavirus was detected in 52 of the 329 (15.8%) patients attending hospital OPDs, and in 11 of the 38 (28.9%) patients attending GPs. Rotavirus was detected in the faecal sample of only one child from each of the two control groups getting treatment in the two facilities respectively. The proportion of patients, who attended the GPs showing only rotavirus and no pathogenic bacteria in their stools, was significantly (Chi-square test at the level of 5%) higher than that in similar patients attending the hospital OPDs. Patients aged 7 to 12 months showed the highest frequency (34%) of rotavirus positive stools. Of the 63 rotavirus positive cases, 19 had mixed infections with commonly occurring bacterial pathogens of the intestines.

Molecular characterization of porcine rotaviruses from the southern region of Brazil: characterization of an atypical genotype G[9] strain.

The G (VP7) and P (VP4) serotype distribution of Brazilian porcine rotaviruses was determined using reverse transcription-PCR genotyping methods. Common porcine G types G3, G4, and G5 were detected in combination with P types [6] and [7]. The detection of nonporcine G types and unusual G-P combinations and the characterization of an atypical virus indicated that interspecies transmission may contribute to the genetic diversity of porcine rotaviruses.

Immunological factors in milk from Brazilian mothers delivering small-for-date term neonates.

Breast milk samples from three groups of Brazilian women were evaluated: G1, mothers delivering term babies of low birth weight (n = 16); G2, mothers delivering preterm babies of appropriate birth weight (n = 20); G3, mothers delivering term babies of appropriate birth weight (n = 30). Milk samples were obtained at 48 h and on the 7th, 15th, 30th and 60th days after delivery and they were analyzed for lysozyme and total IgA levels and for the presence of specific antibodies against Poliovirus types I, II, III, Rotavirus, Herpes simplex virus, Varicella zoster and Cytomegalovirus. The groups were not statistically different in relation to mother's age, parity, type of delivery or socio-economic levels. IgA levels were higher in both low-birth-weight groups (G1 & G2) compared to the control group (G3) throughout the study period. Lysozyme levels decreased up to the 15th day, increasing thereafter up to the 60th day in all groups. Specific antibodies were detected throughout the study period, with no differences among groups. We conclude that breast milk composition of mothers delivering low-birth-weight babies (G1 & G2) was similar despite the different gestational ages.

Electrophoretic study of the genome of human rotaviruses from Rio de Janeiro, São Paulo and Pará, Brazil.

Human rotaviruses from the states of Rio de Janeiro, São Paulo and Pará of Brazil were analysed by RNA electrophoresis. At least some bands characteristic of rotavirus double-stranded RNA were detected in 138 (86.8%) of 159 faecal samples in which the presence of rotavirus had been demonstrated by enzyme immunoassay. Of the RNA-positive samples, 18 (13.0%) were classified as subgroup 1, 94 (68.1%) as subgroup 2, and 26 (18.8%) could not be classified due to absence of visible bands 10 and 11. Subgroup 2 was more frequent in the three states. All strains of subgroup 1 detected in Rio de Janeiro were associated with a single short-lived school outbreak. All strains of subgroup 1 resembled each other in electrophoretic pattern, irrespective of geographical origin, although minor differences could be detected by co-electrophoresis. Subgroup 2, on the other hand, showed a great degree of electrophoretic heterogeneity and could be divided into several sub-categories.

Molecular and serological characterization of group a rotavirus isolates obtained from hospitalized children in Goiânia, Brazil, 1998-2000.

Fecal samples positive for rotavirus group A ( n=120) were analyzed by enzyme immunoassay-monoclonal antibody (EIA-MAb) serotyping and/or reverse transcription/multiplex polymerase chain reaction (PCR) amplification to determine the prevalence of the [P] and G genotypes. The most prevalent G genotype/serotype detected was G1 (76.7%), followed by G2 (5.0%). Six samples were characterized as G9 by multiplex PCR, and one sample was characterized as G3 by EIA-MAb. The combinations of [P] and G genotypes found were P[8] and G1 (20.8%), P[6] and G1 (10.8%), P[6] and G9 (4.2%), P[8] and G2 (1.7%), and P[6] and G2 (0.8%). The diversity of rotavirus group A [P] and G genotypes/serotypes reinforces the need for continuous characterization of rotaviruses circulating in populations in Brazil.

Caracterizaçäo eletroforética e análise de subgrupo de rotavírus em rebanhos bovinos leiteiros do Estado de Säo Paulo / Eletrophoretical characterization and subgroup analysis of rotavirus in dairy cattle in the State of Säo Paulo, Brazil

Foi realizado um estudo para determinar a ocorrência de infecçäo por rotavírus em rebanhos bovinos leiteiros. Foram analisadas 375 amostras de fezes de bezerros, na faixa etária 1 a 45 dias, provenientes de animais pertencentes a nove propriedades rurais, situadas em seis municípios da regiäo nordeste do Estado de Sao Paulo. Destas, 193 pertenciam a animais com diarréia e 182 foram obtidas de animais clinicamente sadios. As técnicas utilizadas para a detecçäo de rotavírus foram o ensaio imunoenzimático (EIE) e a eletroforese em gel de poliacrilamida (EGPA). Por meio do EIE foram detectadas 11,2 por cento (42/375) de amostras positivas, 15 por cento delas (29/193) obtidas de animais com diarréia e 7,1 por cento (13/182) colhidas de animais sem diarréia. A análise do perfil do genoma indicou a presença de seis eletroferótipos distintos, característicos de rotavírus do grupo A. Um único eletroferótipo foi detectado em três rebanhos, o qual permaneceu constante durante o período de amostragem. Em dois rebanhos diferentes eletroferótipos foram detectados, embora com maior prevalência de um dado perfil. A caracterizaçäo das amostras positivas em subgrupos foi realizada por meio do EIE com "duplo sanduíche", utilizando-se anticorpos monoclonais (MAb) específicos para antígenos de subgrupo (I e II). Foram caracterizadas como subgrupo I 52,4 por cento (22/42) das amostras testadas, nenhuma reagiu com MAb de subgrupo II, enquanto as demais, 47,6 por cento (20/42), näo reagiram com nenhum dos dois subgrupos

Genotyping of group A rotavirus samples from Brazilian children by probe hybridization

The G genotyping of 74 group A rotavirus samples was done by RNA-DNA hybridization (dot-blot) using oligonucleotide probes for the VP7 gene region of the human rotavirus serotypes/genotypes 1, 2, 3 and 4. Thirty-one samples could be genotyped by dot-blot showing the following results: G1 = 16, G4 = 6, G3 = 5, and G2 = 4. The data show circulation of genotypes G1-G4 and the predominance of G1. The knowledge of genotypes provides important information concerning rotavirus circulation in Central Brazil

Estudo eletroforético do genoma de rotavírus de suínos do estado de Säo Paulo, Brasil / Electrophoretic study of the genome of porcine rataviruses from Säo Paulo, Brazil

Foi relizado um estudo sobre os eletroferótipos de RNA de rotavírus em suínos, no Estado de Säo Paulo, Brasil. As amostras de fezes foram coletadas de abril a agosto de 1985, em 5 municípios (grupo x) e em abril de 1986, em Bragança Paulista (grupo y). Os rotavírus foram identificados em 45 amostras de um total de 140 amostras analisadas pela eletroforese em gel de poliacrilamida (PAGE) e ensaio imunoenzimático (EIARA). Todas as amostras identificadas pertenciam ao grupo A de rotavírus. A grupo x incluiu 113 amostras de 5 diferentes municípios, coletadas em datas diferentes, com 27 (23,9 por cento) amostras positivas para rotavírus e 3 tipos eletroforéticos diferentes. O grupo y inclui 27 amostras, coletadas de 2 granjas no mesmo município, em um único dia, resultando em 18 (66,7 por cento) amostras positivas para rotavírus, 14 das quais pertenciam ao mesmo tipo. Os resultados do grupo y indicam a ocorrência de um surto epidemológico neste município, causado pelo mesmo tipo de vírus: este é o primeiro relato de tal ocorrência no brasil. Foi detectado um aumento da susceptibilidade dos animais à infecçäo por rotavírus a partir de 15 dias de idade, em ambos os grupos estudados.