The circulation of human astrovirus genotypes in the Central West Region of Brazil

Out of 1,588 faecal samples of children taken from three locations of the Central West Region of Brazil, 57 were positive for astroviruses (HAstVs) using reverse transcription-polymerase chain reaction (RT-PCR). They were genotyped by nested RT-PCR and/or genomic sequencing. HAstV-1 (42.8 percent), HAstV-2 (23.2 percent), HAstV-3 (3.6 percent), HAstV-4 (14.3 percent) and HAstVs -5, -6, -7 and -8 (1.8 percent each) were detected. In Goiânia and Campo Grande, HAstV-1 was the most frequently detected genotype while in Brasília (DF) it was HAstV-2. Shifts in the circulation of astrovirus genotypes were observed in DF and Campo Grande. All samples collected by rectal swabs were viral negative. The astrovirus genotypes were detected in all age groups and there was no correlation between genotype and age group.

Molecular characterization of the NSP4 gene of human group A rotavirus samples from the West Central region of Brazil

Nonstructural protein 4 (NSP4), encoded by group A rotavirus genome segment 10, is a multifunctional protein and the first recognized virus-encoded enterotoxin. The NSP4 gene has been sequenced, and five distinct genetic groups have been described: genotypes A-E. NSP4 genotypes A, B, and C have been detected in humans. In this study, the NSP4-encoding gene of human rotavirus strains of different G and P genotypes collected from children between 1987 and 2003 in three cities of West Central region of Brazil was characterized. NSP4 gene of 153 rotavirus-positive fecal samples was amplified by reverse transcriptase-polymerase chain reaction and then sequenced. For phylogenetic analysis, NSP4 nucleotide sequences of these samples were compared to nucleotide sequences of reference strains available in GenBank. Two distinct NSP4 genotypes could be identified: 141 (92.2 percent) sequences clustered with NSP4 genotype B, and 12 sequences (7.8 percent) clustered with NSP4 genotype A. These results reinforce that further investigations are needed to assess the validity of NSP4 as a suitable target for epidemiologic surveillance of rotavirus infections and vaccine development.

Astrovirus infection in children living in the Central West region of Brazil

This study presents data regarding the circulation of astrovirus in Goiânia-GO and Brasília-DF. These viruses were detected in fecal samples from hospitalized children up to five years old with and without acute gastroenteritis. A total of 1244 fecal samples were collected in two periods, 1994 to 1996 (Brasília) and 1998 to 2002 (Goiânia and Brasília), and were analyzed for viral RNA using the reverse transcription-polymerase chain reaction (RT-PCR). Positivity rates of 4.3 and 0.5 percent for astrovirus were observed in children with acute gastroenteritis and those without gastroenteritis, respectively. Among children with gastroenteritis no statistically significant difference was seen with regards to viral positivity rates in relation to gender and age. However, a higher incidence rate was observed for children from Brasília aged 36 months or more. Overall, astroviruses occurred predominantly from September to March in the two cities, suggesting a seasonal pattern for these viruses which coincides with the highest relative air humidity period. The results of this study highlight the importance of astrovirus as an etiologic agent of acute gastroenteritis in children of the Central West region of Brazil.

Detection of calicivirus from fecal samples from children with acute gastroenteritis in the West Central region of Brazil

The objective of this study was to describe the circulation of caliciviruses in the West Central region of Brazil and its correlation with children's gender and age, as well as with the year and months of the sample collection. Reverse transcriptase-polymerase chain reaction was performed to detect the human calicivirus genome in 1006 fecal samples that were collected in Goiânia (n = 696) and Brasília (n = 310). Viral RNA was detected in 8.6 percent of the samples. No significant difference in viral prevalence was found regarding gender, age or year of the sample. However, it was observed that in Goiânia, there is a higher incidence of caliciviruses from September to March. The analysis employing three primer pairs demonstrated that the Ni/E3 or JV12/13 primer pairs, which detect norovirus (NoV), detected 41 positive samples while the 289/290 primer pair, which detects NoV or sapovirus, detected the remaining 46 samples. Calicivirus circulates in the West Central region of Brazil and for better detection of this virus it is important to use more than one primer pair. Also, we conclude that the seasonality presented by this virus is related to higher humidity in the period.

Avaliaçäo da terapia de reidrataçäo oral (TRO) com soluçäo de 90 miliequivalentes de sódio por litro em crianças de Manaus / Evaluation of oral rehydration with solution of 90 miliequivalent of sodium per litre in children of Manaus

O presente trabalho testou a eficácia e a tolerabilidade de uma soluçäo hidroeletrolítica glicosada, com 90 mEq de sódio por litro, em 25 crianças de uma comunidade pobre de Manaus-AM. Descreve-se a metodologia e as características da amostra estudada. Os resultados da TRO, a nível domiciliar, mostraram que 84% das crianças estavam adequadamente reidratadas em 5 horas de administraçäo da soluçäo e 100% em 24 horas. Todas as crianças aceitaram bem a soluçäo oral, näo tendo sido verificada qualquer reaçäo adversa à mesma. Os resultados säo muito satisfatórios, considerando-se o baixo nível sócio-econômico e a alta incidência de analfabetismo materno presente no bairro periférico deste estudo. Considera-se importante o uso persistente do hidratante oral, a orientaçäo de realimentaçäo precoce das crianças com sua dieta habitual, evitando-se assim pausas alimentares prolongadas ou alimentos inadequados e deletérios para as necessidades nutricionais dessas comunidades

Etiologia das diarréias agudas em Manaus: observaçöes ambulatoriais e na comunidade / Etiology of acute diarrheia in Manaus: observations in the outpatient clinics and in the community

Enteropatógenos foram investigados em 309 amostras de fezes diarréicas, de crianças de zero a seis anos de idade: 109 coletadas em ambulatório e 200 obtidas através de visitas domiciliares à comunidades péri-urbanas de Manaus. A mais alta incidência de diarréia foi observada na faixa etária de zero a 5 meses de idade, tanto em ambulatório como na comunidade. Os enteropatógenos mais frequentemente isolados foram Shigella sp. nos casos ambulatoriais e Escherichia coli enterotoxigênica, na comunidade