Rotavirus subgroups, G serotypes, and electrophoretypes in cases of nosocomial infantile diarrhoea in Belém, Brazil.

From November 1992 to November 1994 stool samples were obtained from 237 children admitted to a public hospital in Belém. Rotaviruses were detected in 19.3 per cent (60/310) of faecal samples. Of these, 32.1 per cent (18/56), 20.9 per cent (38/181), and 5.4 per cent (4/73) were recorded in cases of nosocomial diarrhoea, community-acquired diarrhoea, and controls, respectively. Fifty-two (86.7 per cent) of the 60 rotavirus-positive specimens were subgrouped and the G serotypes of 55 (91.7 per cent) of them were determined. Subgroups I and II were detected in 50 per cent each of the 52 subgrouped strains. G type 2 was present in 46 (83.6 per cent) of the 55 serotyped samples; serotypes G1 and (mixed) G1 and G4 were found in 14.5 per cent and 1.8 per cent, respectively, of these specimens. Viral RNA electrophoresis showed 14 distinct patterns, including 56.7 per cent (34/60) and 43.3 per cent (26/60) of long and short profiles, respectively. In 40 (66.6 per cent) of the 60 rotavirus-positive faecal samples no enteropathogens other than rotavirus were detected. There was an increased incidence of rotavirus infection from July 1993 to February 1994. The rotavirus-related episodes of diarrhoea were more severe than those of other aetiology and greater clinical severity was not related to a specific G type, subgroup, or electrophoretype.

Concomitant rotavirus serotypes 1 and 4 infections in a diarrhoeic from Belem, Brazil

Infeccoes simultaneas por sorotipos 1 e 4 de rotavirus foram observadas em uma crianca de 15 meses de idade, do sexo feminino, internada com diarreia aguda contraida na comunidade que perdurou por 7 dias, evoluindo com desidratacao moderada. As evidencias dessas infeccoes foram inferidas baseadas em testes tais como: a) ensaio imunoenzimatico (ELISA), evidenciando-se reacao positiva para os sorotipos 1 e 4; e b) migracoes extras de segmentos de ARN visualizados a eletroforese em gel de poliacrilamida (EGPA). Esses resultados sugerem que as condicoes precarias de higiene e saneamento em que vivia essa crianca propiciam a infeccao macica por esses agentes virais. Alem disso, a co-circulacao de diferentes sorotipos no mesmo ambiente sustenta a necessidade de utilizar-se, no futuro, uma vacina polivalente, que proteja as criancas contra os quatro sorotipos G, epidemiologicamente importantes

Concomitant rotavirus serotypes 1 and 4 infections in a diarrhoeic child from Belém, Brazil.

Concomitant serotypes 1 and 4 infections were detected in a 15-month old female child with community-acquired diarrhoea which lasted 7 days and coursed with moderate dehydration. The evidence for dual rotavirus infection was offered by the following findings: a) enzyme-linked immunosorbent assay (ELISA) positive reactions to both 1 and 4 serotypes; and b) extra-migrating bands at electrophoresis of RNA in polyacrylamide gel (PAGE). These results suggest that children living under poor sanitation conditions are heavily exposed to rotavirus infections; in addition, the co-circulation of different serotypes in the same setting sustains the current concept that a rotavirus vaccine should be multivalent, in order to protect children against the four epidemiologically important rotavirus G serotypes.

Association of human herpesvirus 6 infection with exanthem subitum in Belem, Brazil

Infeccao recente por hipervirus humano tipo 6 (HHV-6) foi detectada em casos de exantema subito envolvendo quatro criancas com idades de 10 a 24 meses, no periodo compreendido entre abril e agosto de 1994, em Belem, Brasil. Utilizando-se a tecnica da imunofluorecencia indireta, aumentos significativos (de pelo menos oito vezes) foram observadas nas concentracoes de anticorpos das amostras de soro, da fase aguda para as da convalescente, com oito titulos variando de <1:10 / 1:80 a < 1:10 / 1:640 (pacientes 3 e 2, respectivamente). Todas as criancas apresentaram febre alta (acima de 39ºC) por tres dias, seguida de exantema maculo-papular generalizado. O exame fisico realizado nas criancas revelou concomitancia de adenomegalia cervical e amigdalite em dois desses individuos.

Association of human herpesvirus 6 infection with exanthem subitum in Belem, Brazil.

Recent human herpesvirus 6 (HHV-6) infection was detected in cases of exanthem subitum (ES) involving four children, aged 10 to 24 months, between April and August 1994, in Belém, Brazil. By using the indirect immunofluorescence antibody assay (IFA), significant increases (at least eight times) in antibody concentrations were noted from the acute to the convalescent serum samples, with titers ranging from < 1:10/1:80 to < 1:10/1:640 (patients 3 and 2, respectively). All children had high fever (over 39 degrees C) for three days, followed by generalized, maculo-papular skin rash. A physical examination of the children also revealed concomitant, cervical lymph node swelling and tonsillar pharyngitis in two of them.

Rotaviruses as a cause of nosocomial, infantile diarrhoea in northern Brazil: pilot study.

Faecal samples were obtained from 190 children, aged 0 to 5 years, admitted to a public hospital in Belém, Pará, Brazil. These patients were placed in a pediatric ward with 40 beds distributed in six rooms. Cases were classified into three groups: (a) nosocomial: children who developed gastroenteritis 72 hr or later after admission; (b) community-acquired: patients admitted either with diarrhoea or who had diarrhoea within 72 hr following admission; (c) non-diarrhoeic: those children who had no diarrhoea three days before and three days after collection of formed faecal sample. Specimens were routinely processed for the presence of rotaviruses, bacteria and parasites. Rotaviruses were detected through enzyme-linked immunosorbent assay (ELISA) and subsequently serotyped/electrophoretyped. Rotaviruses were the most prevalent enteropathogens among nosocomial cases, accounting for 39% (9/23) of diarrhoeal episodes; on the other hand, rotaviruses occurred in 8.3% (11/133) and 9% (3/34) of community-acquired and non-diarrhoeic categories, respectively. Mixed infections involving rotavirus and Giardia intestinalis and rotavirus plus G. intestinalis and Entamoeba histolytica were detected in frequencies of 8.6 and 4.3%, respectively, in the nosocomial group. The absence of bacterial pathogens in this category, and the unusual low prevalence of these agents in the other two groups may reflect the early and routine administration of antibiotics following admission to this hospital. Rotavirus serotype 2 prevailed over the other types, accounting for 77.8% of isolates from nosocomial diarrhoeal episodes. In addition, at least five different genomic profiles could be observed, of which one displayed an unusual five-segment first RNA cluster. Dehydration was recorded in all cases of hospital-acquired, rotavirus-associated diarrhoea, whereas in only 57% of nosocomial cases of other aetiology. It was also noted that nosocomial, rotavirus-associated diarrhoeal episodes occur earlier (7 days), following admission, if compared with those hospital-acquired cases of other aetiology (14 days).

Nosocomial transmission of an avian-like rotavirus strain among children in Belém, Brazil.

An atypical group-A rotavirus strain, with an electrophoretype displaying 5 segments in the first dsRNA size class, was detected among 3 hospitalized children less than 2 years old. Detection occurred initially 24 h after admission in a non-diarrhoeic child hospitalized because of acute respiratory infection. The second detection involved a child who occupied a different room within the same ward and who developed nosocomial diarrhoea 48 h later. A third case, also of hospital-acquired diarrhoea, was recorded in a child who occupied a bed in the same room as the second case and developed gastroenteritis 24 h following the second case's detection. In addition to the unusual, avian-like genomic profile, the strain was classified as serotype 2, based on a human VP7-specific enzyme-linked immunosorbent assay (ELISA). The question of whether these events reflect either a genomic rearrangement of a human rotavirus strain or a possible interspecies transmission will be further investigated through hybridization assays.