Nine hundred and forty-eight serum samples from 83 children living in Belem, Brazil, collected within their first three years of life, were tested for the presence of group-specific rotavirus-antibody by an enzyme-linked immunosorbent assay (ELISA) blocking-test. Passively transferred maternal antibody lasted about two and half months; subsequently, low levels of rotavirus antibody started to appear at seven months, reaching a peak at eleven months of age. From one year onwards positivity gradually increased, reaching highest values at 34 months of life. Individual responses were examined in sera from 61 children who were followed up since birth to three years of age: 38 (62.3%) of them developed a long-term immunity following first infection; eleven (18.0%) children developed a short-term immunity after first infection by rotavirus; seven (11.5%) had no antibody response within their first three years of life; and 5 (8.2%) showed positive antibody response from birth to three years old.

Prospective study of rotavirus infections in Belém, Pará, Brazil: clinical and epidemiological features Resumo Um estudo prospectivo acerca das diarréias agudas foi levado a efeito no período de abril de 1990 a setembro de 1992, com o propósito primário de avaliar a imunogenicidade, inocuidade e eficácia de uma candidata a vacina para rotavírus, tetravalente, recombinante símio-humana ("RRV-TV"), envolvendo 540 crianças habitantes de Belém, Pará, Brasil. Considerando que metade desses indivíduos recebeu placebo, tal investigação ensejou a oportunidade de ampliar-se o conhecimento clínico-epidemiológico das infecções por esses agentes na região. Foram registrados 2.789 episódios de diarréia no período acima citado. Desse total, 86 (3,1%) se revelaram associados a rotavírus, com destaque para o sorotipo 1, que concorreu com 67,9% dos casos em que foi possível proceder-se à sorotipagem. Taxas de diarréia por criança/ano de 5,9 e 0,2 foram relacionadas ao total de episódios e os positivos para rotavírus, respectivamente. Aliás, esses agentes foram detectados isoladamente em 70,9% dos 86 casos em que se denotou positividade. Quanto às associações com outros enteropatógenos, prevaleceram os casos em que se identificaram G. intestinalis e E. coli enteropatogênicas, concorrendo com 7,0% e 11,6% das infecções mistas, respectivamente. As taxas mensais de diarréias ocasionadas por rotavírus variaram de 0,8 a 9,6%, com picos de incidência durante os meses mais secos do ano. Valores médios dos escores clínicos de 9,4 e 5,3 foram demonstrados para os casos positivos e negativos para rotavírus, respectivamente.J. pediatr. (Rio). 1994; 70(4):220-225: rotavírus, clínica, epidemiologia.

No abstract

The human fecal microbiome is composed of endogenous bacteria, eukaryotic viruses, bacteriophages and retroviruses. Several pathological conditions, including gastroenteritis, may be characterized by imbalance of gastrointestinal functions, with alteration in the diversity and composition of the fecal microbiota. Were analyzed twenty-seven fecal microbiome in children hospitalized with gastroenteritis (norovirus positive) from northern region of Brazil. After sequencing, was verified the presence of the domains Bacteria (95%) and Eukaryota (3.1%), the viruses represented 1.9%. Among the pathogenic viruses were found in addition to noroviruses the picornaviruses, enterovirus and parechovirus. The bacteriophages detected were of Caudovirales order, families Siphoviridae, Podoviridae and Myoviridae. In 22.2% (6/27) of the samples was observed co-infection between norovirus, enterovirus B and echovirus. As for the others components of the microbiome, we can highlight the presence of the taxonomic groups: Terrabacteria (50.2%), composed mainly of Actinobacteria and Firmicutes; Proteobacteria (34.5%) represented by the Enterobacteriaceae family; and FCB group (22%) whose most abundant microorganisms were those of the phylum Bacterioidetes. We performed a metagenomic approach to analyze the fecal microbiota of children with viral gastroenteritis, it was observed that the bacterias (Enterobacteriaceae) deserve attention in a possible association with noroviruses, as they were found in large quantities in infections. In addition, other enteric viruses were observed, such as enteroviruses.