OBJETIVO: Comparar a gravidade de infecções causadas por um único vírus (VSR) com a gravidade de coinfecções. MÉTODOS: Este estudo avaliou uma coorte histórica de lactentes com infecção aguda por VSR. Secreção de nasofaringe foi coletada de todos os pacientes rotineiramente para pesquisa viral usando técnicas de biologia molecular. Os seguintes desfechos foram analisados: tempo total de internação, duração da oxigenioterapia, admissão em unidade de terapia intensiva e uso de ventilação mecânica. Os resultados foram ajustados para os fatores confundidores (prematuridade, idade e aleitamento materno). RESULTADOS: Foram incluídos no estudo 176 lactentes com idade média de 4,5 meses e diagnósticos de bronquiolite e/ou pneumonia. Cento e vinte e um tinham infecção única por VSR, e 55 tinham coinfecções (24 VSR + adenovírus, 16 VSR + metapneumovírus humano e 15 outras associações menos frequentes). Os quatro desfechos de gravidade avaliados foram semelhantes entre o grupo com infecção única por VSR e os grupos com coinfecções, independente do tipo de vírus associado com o VSR. CONCLUSÃO: As coinfecções virais não parecem alterar o prognóstico de lactentes hospitalizados com infecção aguda por VSR.

OBJECTIVE: To compare the severity of single respiratory syncytial virus (RSV) infections with that of coinfections. METHODS: A historical cohort was studied, including hospitalized infants with acute RSV infection. Nasopharyngeal aspirate samples were collected from all patients to detect eight respiratory viruses using molecular biology techniques. The following outcomes were analyzed: duration of hospitalization and of oxygen therapy, intensive care unit admission and need of mechanical ventilation. Results were adjusted for confounding factors (prematurity, age and breastfeeding). RESULTS: A hundred and seventy six infants with bronchiolitis and/or pneumonia were included in the study. Their median age was 4.5 months. A hundred and twenty one had single RSV infection and 55 had coinfections (24 RSV + adenovirus, 16 RSV + human metapneumovirus and 15 other less frequent viral associations). The four severity outcomes under study were similar in the group with single RSV infection and in the coinfection groups, independently of what virus was associated with RSV. CONCLUSION: Virus coinfections do not seem to affect the prognosis of hospitalized infants with acute RSV infection.

The purpose of this work was to acquire an overview of the infectious cycle of HAdV-41 in permissive HEK 293 cells and compare it to that observed with the prototype of the genus, Human adenovirus C HAdV-2. HEK 293 cells were infected with each virus separately and were harvested every 12 h for seven days. Infection kinetics were analysed using confocal and electronic microscopy. The results show that, when properly cultivated, HAdV-41 was not fastidious. It had a longer multiplication cycle, which resulted in the release of complete viral particles and viral stocks reached high titres. After 60 h of infection, the export of viral proteins from the infected cell to the extracellular milieu was observed, with a pattern similar to that previously described for HAdV-2 penton-base trafficking after 30 h of infection. HAdV-41 had a non-lytic cycle and the infection spread from the first infected cell to its neighbours. The release process of the viral particles is unknown. The results observed for HAdV-41 infection in HEK 293 cells show how different this virus is from the prototype HAdV-2 and provides information for the development of this vector for use in gene therapy.

O objetivo do estudo foi verificar a ocorrência e a distribuição anual de adenovírus humanos e vírus da Hepatite A (VHA) no efluente doméstico da cidade de Limeira, São Paulo, ao longo do período de Dezembro de 2004 e Dezembro de 2005, com vistas à futura implementação de sistemas de tratmento de água de esgoto. Cinquenta amostras de efluente bruto com volume de 8L cada foram colhidas semanalmente e os vírus concentrados por filtração em membrana eletropositiva ZP60S, seguida de ultracentrifugação. Adenovírus foram detectados por PCR e nested-PCR. Adenovírus da espécie F foram distinguidos das demais por restrição do produto da PCR com endonuclease TaqI. Ensaios de infectividade viral foram realizados em culturas de células HEp-2. A presença do vírus da hepatite A também foi pesquisada nas mesmas amostras, fazendo-se uso de método de RT-PCR. Adenovírus foram detectados em todas as amostras, sendo a espécie F identificada em 82% destas. Sessenta e quatro por cento dos adenovírus detectados ainda estavam infecciosos. O vírus da Hepatite A foi detectado em 48% das amostras examinadas. Estes resultados evidenciam a presença e a circulação de Adenovírus humano e VHA nas águas de esgoto doméstico de Limeira ao longo do período de estudo, demonstrando a importância de um tratamento adequado desse material antes da disposição no meio ambiente.

The aim of this study was to verify the presence and annual distribution of adenoviruses and hepatitis A virus in domestic sewage in the city of Limeira, São Paulo. Fifty samples with a volume of 8 liters each were collected weekly from December 2004 to December 2005. The viruses were concentrated by filtration through positively charged ZP60S filter membranes, followed by ultracentrifugation. Human adenoviruses (HAdV) were detected by PCR followed by nested-PCR and screening for species F was done by restriction of the PCR product with TaqI endonuclease. Virus infectivity assays were performed by inoculation of concentrates onto HEp-2 cell monolayers. RT-PCR was used for the detection of hepatitis A virus. HAdV were detected in all samples, and 64% of samples were positive for infectious virus. Species F was present in 82% of the samples. Hepatitis A virus was detected in 48% of the samples. These results demonstrate that HAdV and HAV were present in the domestic sewage of Limeira throughout the period of study, demonstrating the importance of an adequate treatment before the disposal in the environment.

Human adenovirus (HAdV) and human respiratory syncytial virus (HRSV) are important etiologic agents of acute respiratory infections. In this study, a duplex polymerase chain reaction (PCR) assay was developed for the simultaneous detection of HAdV and HRSV in clinical samples. Sixty previously screened nasopharyngeal aspirates were used: 20 HAdV-positive, 20 HRSV-positive and 20 double-negative controls. Eight samples were positive for both viruses. The duplex PCR assay proved to be as sensitive and specific as single-target assays and also detected the mixed infections with certainty. The identification of both viruses in a single reaction offers a reduction in both cost and laboratory diagnostic time.