Characterization of human metapneumoviruses isolated from patients in North America.

Human metapneumovirus (HMPV) was recently identified in The Netherlands and was linked to acute respiratory tract illness. In this study, 11 isolates from 10 patients with respiratory disease from Quebec, Canada, were tested by a reverse-transcriptase polymerase chain reaction based on the fusion protein gene. Identified sequences were consistent with HMPV. The patients were 2 months to 87 years of age (median age, 58 years) and presented with acute respiratory tract illness during the winter season. Sequence studies of the nucleocapsid, fusion, and polymerase genes identified 2 main lineages of HMPV and cocirculation of both lineages during the same year. These findings support a previous finding that HMPV is a human respiratory pathogen that merits further study

Clinical patterns and seasonal trends in respiratory syncytial virus hospitalizations in São Paulo, Brazil Padrões clínicos e sazonalidade das hospitalizações causadas pelo vírus respiratório sincicial em São Paulo, Brasil

The respiratory viruses are recognized as the most frequent lower respiratory tract pathogens for infants and young children in developed countries but less is known for developing populations. The authors conducted a prospective study to evaluate the occurrence, clinical patterns, and seasonal trends of viral infections among hospitalized children with lower respiratory tract disease (Group A). The presence of respiratory viruses in children's nasopharyngeal was assessed at admission in a pediatric ward. Cell cultures and immunofluorescence assays were used for viral identification. Complementary tests included blood and pleural cultures conducted for bacterial investigation. Clinical data and radiological exams were recorded at admission and throughout the hospitalization period. To better evaluate the results, a non- respiratory group of patients (Group B) was also constituted for comparison. Starting in February 1995, during a period of 18 months, 414 children were included- 239 in Group A and 175 in Group B. In Group A, 111 children (46.4%) had 114 viruses detected while only 5 children (2.9%) presented viruses in Group B. Respiratory Syncytial Virus was detected in 100 children from Group A (41.8%), Adenovirus in 11 (4.6%), Influenza A virus in 2 (0.8%), and Parainfluenza virus in one child (0.4%). In Group A, aerobic bacteria were found in 14 cases (5.8%). Respiratory Syncytial Virus was associated to other viruses and/or bacteria in six cases. There were two seasonal trends for Respiratory Syncytial Virus cases, which peaked in May and June. All children affected by the virus were younger than 3 years of age, mostly less than one year old. Episodic diffuse bronchial commitment and/or focal alveolar condensation were the clinical patterns more often associated to Respiratory Syncytial Virus cases. All children from Group A survived. In conclusion, it was observed that Respiratory Syncytial Virus was the most frequent pathogen found in hospitalized children admitted for severe respiratory diseases. Affected children were predominantly infants and boys presenting bronchiolitis and focal pneumonias. Similarly to what occurs in other subtropical regions, the virus outbreaks peak in the fall and their occurrence extends to the winter, which parallels an increase in hospital admissions due to respiratory diseases.<br>Os vírus respiratórios são reconhecidos como os mais frequentes patógenos do trato respiratório inferior para lactentes e crianças de idade reduzida em países desenvolvidos, mas o conhecimento sobre este fato é menor nos países em desenvolvimento.Os autores realizaram um estudo prospectivo para avaliar a ocorrência, os padrões clínicos e a sazonalidade das infecções virais entre as crianças hospitalizadas com doença do trato respiratório inferior (grupo A). A presença de vírus respiratórios na nasofaringe das crianças foi avaliada à admissão em uma enfermaria de pediatria. A cultura celular e a imunofluorescência foram utilizadas para identificação viral. Exames complementares incluiram culturas de sangue e líquido pleural para detecção de bactérias. Dados clínicos e exames radiológicos foram anotados na admissão e durante o período de internação. Para avaliar adequadamente os resultados foi constituído um grupo sem doença respiratória para comparação. Com início em fevereiro de 1995, durante um período de 18 meses, 414 crianças foram incluídas - 239 no grupo A e 175 no grupo B. No grupo A, 111 crianças (46,4%) tinham vírus enquanto somente 5 (2,9%) apresentavam vírus no grupo B. O Vírus Respiratório Sincicial foi detectado em 100 crianças do grupo A (41,8%), o Adenovírus em 11 (4,6%), o vírus Influenza em 2 (0,8%), e o Parainfluenza em uma criança (0,4%). No grupo A as bactérias foram encontradas em 14 casos (5,8%). O Vírus Respiratório Sincicial estava associado a outro vírus ou bactéria em seis casos. Ocorreram dois surtos de Vírus Respiratório Sincicial, com pico em maio e junho. Todas as crianças acometidas por este vírus tinham idade inferior a 3 anos, na sua maior parte menos de um ano de idade. O acometimento bronquial episódico e difuso e/ou a condensação alveolar focal, foram os padrões clínicos mais frequentemente associados aos casos de infecção pelo Vírus Respiratório Sincicial. Todas as crianças do grupo A sobreviveram. Em conclusão, foi observado que o Vírus Respiratório Sincicial foi o patógeno mais frequentemente encontrado em crianças hospitalizadas por doença respiratória grave. As crianças afetadas eram predominantemente lactentes do sexo masculino com bronquiolite e pneumonias focais. De modo similar ao que ocorre em outras regiões subtropicais os surtos do vírus têm pico no outono, extendem-se ao inverno, e se acompanham de um aumento nas internações hospitalares por doença respiratória

Characterization of a novel coronavirus associated with severe acute respiratory syndrome

In March 2003, a novel coronavirus (SARS-CoV) was discovered in association with cases of severe acute respiratory syndrome (SARS). The sequence of the complete genome of SARS-CoV was determined, and the initial characterization of the viral genome is presented in this report. The genome of SARS-CoV is 29,727 nucleotides in length and has 11 open reading frames, and its genome organization is similar to that of other coronaviruses. Phylogenetic analyses and sequence comparisons showed that SARS-CoV is not closely related to any of the previously characterized coronaviruses