Noroviruses associated with acute gastroenteritis in a children's day care facility in Rio de Janeiro, Brazil

Noroviruses (Norwalk-like viruses) are an important cause of gastroenteritis worldwide. They are the most common cause of outbreaks of gastroenteritis in the adult population and occur in nursing homes for the elderly, geriatric wards, medical wards, and in hotel and restaurant settings. Food-borne outbreaks have also occurred following consumption of contaminated oysters. This study describes the application of a reverse transcription-polymerase chain reaction (RT-PCR) assay using random primers (PdN6) and specific Ni and E3 primers, directed at a small region of the RNA-dependent RNA polymerase-coding region of the norovirus genome, and DNA sequencing for the detection and preliminary characterisation of noroviruses in outbreaks of gastroenteritis in children in Brazil. The outbreak samples were collected from children <5 years of age at the Bertha Lutz children's day care facility at Oswaldo Cruz Foundation (Fiocruz), Rio de Janeiro, that occurred between 1996 and 1998, where no pathogen had been identified. At the Bertha Lutz day care center facility, only Fiocruz's employee children are provided for, and they come from different social, economic and cultural backgrounds. Three distinct genogroup II strains were detected in three outbreaks in 1997/98 and were most closely related to genotypes GII-3 (Mexico virus) and GII-4 (Grimsby virus), both of which have been detected in paediatric and adult outbreaks of gastroenteritis worldwide.

Comparative sequence analysis of the P-, M- and L-coding region of the measles virus CAM-70 live attenuated vaccine strain

Measles virus is a highly contagious agent which causes a major health problem in developing countries. The viral genomic RNA is single-stranded, nonsegmented and of negative polarity. Many live attenuated vaccines for measles virus have been developed using either the prototype Edmonston strain or other locally isolated measles strains. Despite the diverse geographic origins of the vaccine viruses and the different attenuation methods used, there was remarkable sequence similarity of H, F and N genes among all vaccine strains. CAM-70 is a Japanese measles attenuated vaccine strain widely used in Brazilian children and produced by Bio-Manguinhos since 1982. Previous studies have characterized this vaccine biologically and genomically. Nevertheless, only the F, H and N genes have been sequenced. In the present study we have sequenced the remaining P, M and L genes (approximately 1.6, 1.4 and 6.5 kb, respectively) to complete the genomic characterization of CAM-70 and to assess the extent of genetic relationship between CAM-70 and other current vaccines. These genes were amplified using long-range or standard RT-PCR techniques, and the cDNA was cloned and automatically sequenced using the dideoxy chain-termination method. The sequence analysis comparing previously sequenced genotype A strains with the CAM-70 Bio-Manguinhos strain showed a low divergence among them. However, the CAM-70 strains (CAM-70 Bio-Manguinhos and a recently sequenced CAM-70 submaster seed strain) were assigned to a specific group by phylogenetic analysis using the neighbor-joining method. Information about our product at the genomic level is important for monitoring vaccination campaigns and for future studies of measles virus attenuation.

Human parvovirus B19 infection in HIV-positive patients

Parvovirus B19 infects predominantly erythroid cells, leading to transient inhibition of erythropoiesis. Immunocompromised patients may be unable to produce neutralizing antibodies and may develop severe chronic anemia. Epidemiological studies done on Niterói population showed that B19 infection occurs periodically in late spring and summer. We report a study from 55 HIV infected patients attending an infectious diseases outpatient clinic in this city during a 5-month period in which B19 circulation was well documented. All patients were under anti-retroviral therapy. No anti-B19 IgM was found, but a high prevalence of IgG anti-B19 (91%) was observed. In six patients, B19 DNA was found by dot-blot hybridization techniques, but this was not confirmed by PCR. None of these 6 patients manifested anemia and only one had CD4 cell count below 200 x 10(7)/L. We conclude that persistent infection causing anemia is an infrequent finding in our HIV positive patients under drug therapy.

O parvovírus B19 infecta predominantemente células eritróides, causando inibição transitória da eritropoiese. Pacientes imunocomprometidos podem ser incapazes de produzir anticorpos neutralizantes, evoluindo com grave anemia crônica. Estudos epidemiológicos da população de Niterói mostraram que a infecção ocorre periodicamente no final da primavera e no verão. Descrevem-se 55 pacientes infectados pelo HIV atendidos num ambulatório de doenças infecciosas nesta cidade num período de cinco meses, no qual a circulação do parvovírus B19 foi documentada. Todos os pacientes estavam sob terapia anti-retroviral. Não se encontrou IgM anti-B19, mas notou-se uma prevalência alta de IgG anti-B19 (91%). Em seis pacientes verificou-se a presença de DNA do B19 por hibridização em dot-blot, o que não se confirmou por PCR. Nenhum destes seis pacientes tinha anemia, e apenas um tinha células CD4 abaixo de 200 x 107/L. Conclui-se que infecção persistente causando anemia é um achado infreqüente em nossos pacientes HIV positivos sob terapia medicamentosa.

Morphological and virological studies in six autopsies of children with adenovirus pneumonia

Pulmonary lesions compatible with adenovirus infection were detected by gross and microscopic examination of autopsy tissues children aged from 5 to 34 months. Hepatic lesions indicative of systemic infection were also found in four of the chisldren. The viral etiology was confirmed in three cases by in-situ hibridization, electro-microscopy and immunofluorescence performed in parafin-embedded tissues, and in one case by cell culture isolation of adenovirus type 2 from nasopharyngeal exudate. Routine testing by methods additional to conventional light microscopy would probably have revealed a larger number of adenovirus infections among the 1.103 autopsy records analyzed in this study

Aplastic crisis due to human parvovirus B19 infection in hereditary hemolytic anaemia

Specific anti-B19 IgM was demonstrated in sera from three children showing transient aplastic crisis. A two years-old boy living in Rio de Janeiro suffering from sickle-cell anaemia showed the crisis during August, 1990. Two siblings living in Santa Maria, RS, developed aplastic crisis during May, 1991, when they were also diagnosed for hereditary spherocytosis. For a third child from this same family, who first developed aplastic crisis no IgM anti-B19 was detected in her sera

Longitudinal study of acute respiratory diseases in Rio de Janeiro: occurrence of respiratory viruses during four consecutive years

Investigamos, durante um periodo de 4 anos (1982 a 1985), a ocorrencia de virus em secrecoes de nasofaringe coletadas de criancas com menos de 5 anos de idade apresentando quadro clinico de infeccao respiratoria aguda (IRA), residentes na cidade do Rio de Janeiro. Foram encontrados todos os virus conhecidos como associados a IRA, com excessao do virus influenza C e parainfluenza 1, 2 e 4. Virus foram isolados mais frequentemente de criancas internadas em salas de emergencia e enfermarias que daquelas atendidas em ambulatorio. Este fato esta claramente relacionado com a alta incidencia do virus sincicial respiratorio (RSV) nos casos mais severos de IRA. Especimes positivos para RSV aparecem principalmente durante o outono, nos 4 anos consecutivos, indicando uma ocorrencia sazonal. As salas de emergencias sao a melhor fonte de dados para vigilancia do RSV, onde um aumento no numero de casos positivos corresponde a um aumento no numero total de casos de IRA internados. Os adenovirus ocupam o segundo lugar entre os virus frequentemente isolados, sendo predominante os sorotipos 1, 2 e 7. Embora em menor numero os virus influenza e parainfluenza tipo 3 tambem sao encontrados. Virus influenza A foram isolados igualmente em criancas internadas em enfermarias, salas de emergencia e nos pacientes atendidos em...

Estudo da patogenicidade para camundongos recem-nascidos de amostras de echovirus tipo 9 isoladas de casos de meningite durante um surto epidemico no Rio de Janeiro. / Pathogenicity for newborn mice of echovirus type 9 samples isolated from cases of meningitis during an outbreak in Rio de Janeiro

A patogenicidade do echovirus tipo 9 para camundongos recem-nascidos foi estudada, utilizando-se 12 amostras isoladas em cultura de celulas primarias de rim de macaco, a partir do liquor de criancas com meningite. Os animais inoculados com o fluido da primeira passagem em celulas desenvolveram paralisia flacida, apos um periodo de 5 dias, com a morte ate o 8o. dia.Os especimens originais de liquor nao continham suficiente virus para provocar sinais clinicos nos animais inoculados no periodo de 21 dias de observacao. Ao exame histopatologico os animais doentes apresentaram miopatia necrotizante da musculatura paravertebral, lingua e diafragma. Animais inoculados que nao desenvolveram paralisia durante o periodo de observacao apresentaram miosite discreta, sem que tenha sido encontrada necrose das fibras musculares

Single radial haemolysis: a sensitive test for the detection of antibody to influenza B virus.

Foi realizado um estudo sobre anticuerpos para o virus influenza B, em soros de pessoas residentes no Rio de Janeiro, abrangendo todas as faixas etarias. Empregou-se dois testes: inibicao de hemaglutinacao, utilizada rotineiramente na pesquisa de anticorpos para virus influenza; e hemolise radial simples, uma reacao mais recentemente desenvolvida. Esta ultima mostrou-se consideravelmente mais sensivel, demostrando que um quinto das criancas testadas adquiriram a infeccao ate cinco anos e dois tercos ate os dez anos de idade. A maioria dos adultos mostrou anticorpos para influenza B

Influenza surveillance in Rio de Janeiro: a serological study.

Inquerito sorologico para determinacao de anticorpos para tres amostras de virus influenza A que circularam no mundo durante os ultimos anos, foi realizado com especimens coletados no Rio de Janeiro de 1976 a 1980. Anticorpos para A/Victoria/3/75 (H3N2) foram encontrados em maior proporcao durante 1976, um ano apos o seu aparecimento. A frequencia de deteccao de anticorpos para A/Texas/1/77 (H3N2) foi muito baixa, havendo pouca evidencia de que este virus tenha circulado amplamente.Anticorpos para A/USSR/90/77 (H1N1) estavam ausentes em soros de pessoas menores de 20 anos de idade em 1976 e 1977. Em 1978, metade dos soros apresentaram anticorpos detectaveis, e em 1980 somente 40% nao apresentaram, indicando consideravel disseminacao deste virus, embora nao tenha sido detectado na comunidade