Detección de virus parainfluenza en pacientes inmunocomprometidos e inmunocompetentes atendidos en un hospital terciario de la Ciudad de São Paulo, Brasil / Detection of parainfluenza virus in immunocompromised and immunocompetent patients in a tertiary hospital in Sao Paulo, Brazil

Parainfluenza virus infections (PIV) were evaluated in patients with mild and severe infections through real time PCR. One thousand and sixty-seven samples were collected from subjects as follows: 233 adult renal transplanted outpatients, 129 children with congenital heart disease, 381 with adult hematopoietic stem cell patients and 324 hospitalized patients suspected of influenza A (H1N1) pdm09 infection. PIV was detected in 74 (6.9%) samples. VPI-3 was the most frequent (60.8%) and a higher risk was observed for older adults (p = 0.018) and for those who were hematopoietic stem cell transplanted. Further studies are needed to understand the VPI role in patients' at risk for developing serious illness.

Se evaluó la infección por virus parainfluenza (VPI) en pacientes con infecciones leves y graves mediante RPC en tiempo real. Se analizó un total de 1.067 muestras: 233 provenían de pacientes ambulatorios adultos receptores de trasplantes renales, 129 de niños con cardiopatía congénita, 381 de pacientes receptores de trasplantes de precursores hematopoyéticos adultos y 324 de pacientes hospitalizados con sospecha de influenza A (H1N1) pdm09. Se detectó VPI en 74 muestras (6,9%). Siendo VPI-3 el virus más frecuente (60,8%), se observó un mayor riesgo para los adultos mayores (p = 0,018) y para aquellos que fueron receptores de precursores hematopoyéticos. Son necesarios estudios adicionales para entender el papel del VPI en pacientes de riesgo para desarrollar enfermedad grave.

Detection of respiratory viruses by real-time polymerase chain reaction in outpatients with acute respiratory infection

Viruses are the major contributors to the morbidity and mortality of upper and lower acute respiratory infections (ARIs) for all age groups. The aim of this study was to determine the frequencies for a large range of respiratory viruses using a sensitive molecular detection technique in specimens from outpatients of all ages with ARIs. Nasopharyngeal aspirates were obtained from 162 individuals between August 2007-August 2009. Twenty-three pathogenic respiratory agents, 18 respiratory viruses and five bacteria were investigated using multiplex real-time reverse transcriptase polymerase chain reaction (RT-PCR) and indirect immunofluorescence assay (IIF). Through IIF, 33 (20.4%) specimens with respiratory virus were recognised, with influenza virus representing over half of the positive samples. Through a multiplex real-time RT-PCR assay, 88 (54.3%) positive samples were detected; the most prevalent respiratory viral pathogens were influenza, human rhinovirus and respiratory syncytial virus (RSV). Six cases of viral co-detection were observed, mainly involving RSV. The use of multiplex real-time RT-PCR increased the viral detection by 33.9% and revealed a larger number of respiratory viruses implicated in ARI cases, including the most recently described respiratory viruses [human bocavirus, human metapneumovirus, influenza A (H1N1) pdm09 virus, human coronavirus (HCoV) NL63 and HCoV HKU1].

Tracking viral particles in the intestinal contents of the American bullfrog, Lithobates catesbeianus, by Transmission Electron Microscopy / Pesquisa de partículas virais em conteúdo intestinal de rãs-touro americanas, Lithobates catesbeianus, por meio da microscopia eletrônica de transmissão

Feces are an important viral agent elimination route for infected carrier animals and in aquatic organisms these pathogenic agents can very rapidly propagate due to the habitation environment. The objective of this work is to track viral particles in the intestinal contents of bullfrogs (Lithobates catesbeianus) from five commercial frog farms in the region of Vale do Paraíba, in the State of São Paulo, Brazil, using negative contrast transmission electron microscopy (TEM). The Coronaviridae, Paramyxoviridae, Parvoviridae and Herpesviridae families were observed and photographed in specimens. This work emphasizes the importance of adopting sanitary measures in commercial farms and confirms that observing feces by TEM is an efficient and rapid diagnostic tool for detecting viral agents...

Sabendo-se que as fezes são uma importante via de eliminação de agentes virais pelos animais portadores e que, por estarem na água, os agentes patogênicos podem se propagar mais rapidamente, objetivou-se a pesquisa de vírus em conteúdo intestinal de rãs-touro (Lithobates catesbeianus) de cinco ranários comerciais na região do Vale do Paraíba, no estado de São Paulo, pela técnica de microscopia eletrônica de transmissão. As famílias Coronaviridae, Paramixoviridae, Parvoviridae e Herpesviridae foram observadas e fotografadas. Este trabalho ressalta a importância da adoção de medidas sanitárias nas criações, além da confirmação de que a observação de fezes pela microscopia eletrônica de transmissão é uma eficiente ferramenta de diagnóstico rápido para agentes virais...

Recent advances in the study of mechanism of APOBEC3G against virus / 药学学报

APOBEC3 is a class of cytidine deaminase, which is considered as a new member of the innate immune system, and APOBEC3G belongs to this family. The research about APOBEC3G is a new direction of innate immune defense mechanism against virus. APOBEC3G has the restrictive activity on many viral replications, which deaminates dC to dU in the viral genome and then induces extensive hypermutation. APOBEC3G can also interrupt viral replication at several phases such as reverse transcription, replication, nucleocapsid and so on by non-deamination mechanisms. However, virus can encode viral proteins to counteract the restriction activity of APOBEC3G. Elucidation of the antagonistic interaction between APOBEC3G and the virus will be contributed to development of new antiviral drugs in the future.

Avian paramyxoviruses: detection by transmission electron microscopy techniques / Paramixovirus aviario: detección por técnicas de microscopía electrónica de transmisión

Diseases caused by avian paramyxovirus (APMV) occur in commercial, captive and wild birds worldwide, demonstrating the significant economic and ecological importance of these agents. Paramyxoviruses belong to the paramyxoviridae family, paramyxovirinae subfamily and avulavirus genus. During the period 2000 to 2011, stool and small intestine samples of 1647 birds species were sent to the Laboratory of Electron Microscopy, Biological Institute of São Paulo, Brazil, for diagnosis of viral agents. The samples were processed by negative staining (rapid preparation) and resin embedding techniques. Under the transmission electron microscope by negative staining technique, in 294 (17.8 percent) samples of 1647 were visualized paramyxovirus particles pleomorphic, roughly spherical or filamentous, measuring 100 to 500 nm of diameter containing an envelope covered with spikes and characteristic helical herring-bone-like nucleocapsid measuring 15 to 20 nm in diameter. Ultrathin sections of the small intestine fragments revealed the presence of amorphous granular intracytoplasmic inclusions surrounded by membrane and containing viral nucleocapsid measuring 10-14 nm in diameter. Immature particles budding from cell membranes, pleomorphic, spherical and tubular particles containing viral nucleocapsid strands, and the complete particles measured up to 170 nm in diameter were seen in the cytoplasm. Intranuclear inclusions containing viral nucleocapsid were also visualized. Nuclei showed a marginalized chromatin.

Las enfermedades causadas por paramixovirus (APMV) ocurren mundialmente, tanto en aves de corral, en aquellas en vida libre o en cautiverio, lo que demuestra la importancia económica y ecológica de estos virus. El paramixovirus aviario pertenece a la familia paramyxoviridae, subfamilia paramyxovirinae y género avulavirus. Durante el periodo de 2000 a 2011, muestras de heces y fragmentos del intestino delgado de 1647 especies de aves han sido enviados al Laboratorio de Microscopía Electrónica, Instituto Biológico de São Paulo, para el diagnóstico de agentes virales. Las heces y fragmentos del intestino delgado, se procesaron por las técnicas de contraste negativo (preparación rápida) y la inclusión en resina. Al microscopio electrónico de transmisión mediante la técnica de contraste negativo se visualizaron en muestras de 294 aves, partículas de paramixovirus, pleomórficas, más o menos esféricas o filamentosas, de 100 a 500 nm de diámetro que contenían un sobre cubierto por púas que presentaban característica helicoidal, con nucleocapside tipo espiga, midiendo de 15 a 20 nm de diámetro. Secciones ultrafinas de los fragmentos del intestino delgado, revelaron en el citoplasma la presencia de inclusiones granulares amorfas rodeadas por una membrana, contiendo nucleocapside viral midiendo de 10-14 nm de diámetro, partículas inmaduras brotando de las membranas celulares, partículas virales tubulares, esféricas o pleomórficas que contenían filamentos nucleocapside. Estas partículas completas alcanzaban a los 170 nm de diámetro. Fueron observadas también, inclusiones intranucleares contiendo nucleocapside viral. Los núcleos mostraron una cromatina marginal.

Brote de parotiditis en el centro penitenciario La Modelo, de Bogotá, Colombia, septiembre-diciembre de 2011 / In center penitentiary bud of parotiditis the Model, of Bogotá, Colombia, September- December of 2011 / No centro botão da penitenciária do parotiditis o modelo, de Bogotá, Colômbia, Setembro- Dezembro de 2011

Antecedentes: El virus de la parotiditis es un paramyxovirus de la familia Paramyxoviridae. Ingresa al cuerpo humano por las vías respiratorias y se localiza en la glándula parótida, donde se reproduce; su único reservorio es el ser humano. Su contagio se da por contacto directo, a través de goticas infectadas; es altamente contagioso. En este trabajo se describe un brote de parotiditis en la cárcel La Modelo, en Bogotá, Colombia; se describe a las personas enfermas, el tiempo de duración del brote y qué medidas se tomaron para su control; se evaluará la efectividad del programa de notificación epidemiológica, si este responde a las necesidades de poblaciones especiales y qué aprendizajes quedaron de la experiencia en cuanto al control de este brote en particular. Métodos: El presente es un estudio descriptivo transversal sobre el brote de parotiditis en el centro penitenciario (CP) La Modelo, en Bogotá. Se utilizó la información recolectada durante el brote por la Empresa Social del Estado (ese) del Sur y el Nivel Central, de la Secretaria Distrital de Salud (sds) de Bogotá. Resultados: Se presentaron 330 casos de parotiditis entre los 6905 internos que se encontraban durante el periodo septiembre-noviembre de 2011 en el cp, y un caso en un funcionario del área de sanidad de la misma entidad; se reportaron 2 casos de complicaciones derivadas de la parotiditis. Fueron vacunados 4495 internos con vacuna trivalente (srp), y 170, con vacuna doble viral (sr), y de los cuales se reportaron 2 eventos supuestamente atribuibles a vacunación e inmunización (esavi). Conclusión: Un reporte adecuado y oportuno, una óptima sensibilización en todos los componentes del sistema de vigilancia epidemiológica y la aplicación de medidas (entre otras, la vacunación) son necesarios para evitar la propagación de brotes de parotiditis en sitios de condiciones complejas como las cárceles, donde predominan el hacinamiento y ambientes higiénico sanitarios cuestionables.

Background: Mumps is an acute viral disease highly contagious caused by many viruses like Paramixovirus, Parainfluenza and Newcastle. It enters the body through the respiratory tract and is then located in the parotid gland where it reproduces. The only reservoir is the human body and contagion is given by direct contact with inflected droplets. This work describes a mumps outbreak occurred in the prison La Modelo in Bogota-Colombia, a description of the sick people, duration of the outbreak, and the control measures taken in a special population with complex sanitary and hygienic conditions are provided. The effectiveness of the epidemiological notification program is evaluated, as well as the knowledge acquired during the control of this particular outbreak. Methods: This is a descriptive cross-sectional study of the outbreak of mumps in the penitentiary center (cp) La Modelo in Bogota. Information was collected during the outbreak by the Hospital del Sur and the Central Level of the District Health Secretary of Bogota (sds). Results: 330 cases of mumps were registered between September to November 2011 of the 6905 interns in the cp, one case was of a health staff member of the prison, two cases of complications derived from the virus were reported. 4495 interns were vaccinated with trivalent (srp), and 170 with (sr) of which two people developed events supposedly attributable to vaccination and immunization. Conclusions: An optimal sensitization to all components of the prison's epidemiological surveillance system thus warranting an appropriate and timely report, also specific measures like the vaccination are necessary to prevent the spread of mumps outbreak in sites with complex conditions such as a prison where the overcrowding is predominate and were questionable sanitary hygienic environments exist.

Antecedentes: O vírus da caxumba é um paramixovírus da família Paramyxoviridae, entra por via respiratória e está localizado na glândula parótida, onde se reproduz e o único hospedeiro é o homem, seu contágio ocorre com o contato direto por meio de gotículas infectadas e é altamente contagiosa. Este artigo descreve um surto de caxumba ocorrido na prisão La Modelo, em Bogotá ­ Colômbia. Serão relatados os casos de peso as contagiadas, a duração do surto e as medidas tomadas para controlar a doença, como também avaliar a eficácia do programa de controle epidemiológico e se responde às necessidades da população em quesão e a aprendizagem envolvida no controle desse surto em particular. Métodos: caracteriza como um estudo descritivo transversal de um surto de caxumba no Centro Penitenciário (CP) La Modelo, em Bogotá. Foram utilizadas informações coletadas durante o surto pela Empresa Social do Estado (ESE), do Sul e do Nivel Central da Secretaria de Saúde de Bogotá (sds). Resultados: foram diagnosticados 330 casos de caxumba nos 6905 presos durante os meses de setembro a novembro de 2011 no CP, e um caso em um funcionário de saúde da mesma entidade, como também foi apresentado dois casos com complicações relatadas decorrentes caxumba. Foram vacinados 4495 detentos com trivalente (SRP) e 170 com (SR), dos quais foram notificados 2 eventos supostamente atribuíveis à vacinação e imunização (ESAVI). Conclusão: Um relatório adequado, oportuno e uma sensibilização de todo pessoal da vigilância epidemiológica e medidas de aplicação, incluindo a vacinação, são necessários para evitar a propagação do surto de caxumba em locais com condições complexas, tais como prisões, onde domina a superlotação e ambientes higiênicos sanitários questionáveis

Viral research in Brazilian owls (Tyto alba and Rhinoptynx clamator) by transmission electron microscopy / Investigación viral en buhos brasileños (Tyto alba y Rhinoptynx clamator) a través de microscopía electrónica de transmisión

The barn-owl (Tyto Alba) and striped-owl (Rhinoptynx clamator) belong respectively to the families Tytonidae and Strigidae. Avian paramyxoviruses have been isolated from a variety of species of wild and domestic birds wordlwide causing diverse clinical symptoms and signs. Paramyxoviruses belong to the family Paramyxoviridae and Avulovirus genus, including nine serotypes (APMV 1 to 9). The lymphoid leukosis is a retrovirus-induced neoplasia. The avian retroviruses belong to the Retroviridae family and to the Alpharetrovirus genus. Coronaviruses can cause respiratory and enteric disease in several species of birds. They belong to the Coronaviridae family and to the groups 3a e 3c. In this study, we describe the presence of viruses in four owls, two barn owls (Tyto alba) and two striped owls (Rhinoptynx clamator), rescued from tree-lined streets of Sao Paulo, Brazil and sent to the Recovery Center of Wild Animals of the Tietê Ecological Park, where the animals died. Fragments of lung, liver and small intestine of these birds were processed for transmission electron microscopy utilizing negative staining (rapid preparation), immunoelectron microscopy and immunocitochemistry techniques. Under the transmission electron microscopy paramyxovirus particles, pleomorphic, roughly spherical or filamentous, measuring 100 to 500 nm of diameter containing an envelope covered by spikes, an herring-bone helical nucleocapsid-like structure, measuring 15 to 20 nm in diameter, were visualized in the samples of lung, liver and small intestine of all owls. In small intestine samples of the two striped-owl (owls 3 and 4) it was detected pleomorphic coronavirus particles with a diameter of 75-160 nm containing a solar corona-shaped envelope, with projections of approximately 20 nm of diameter. In liver fragments of one striped-owl (owl 4) pleomorphic particles of retrovirus with a diameter of 80-145 nm containing an envelope with short projections and diameter of 9 nm were....

La lechuza (Tyto Alba) y el búho de orejas (Rhinoptynx clamator) pertenecen respectivamente a las familias Strigidae y Tytonidae. El paramixovirus aviario se ha aislado de especies de vida silveste como las aves domésticas por todo el mundo, causando diversos síntomas clínicos. El paramixovirus pertenece a la familia Paramyxoviridae y al Avulovirus genus que incluye nueve serotipos (APMV 1 a 9). La leucosis linfoide es una neoplasia inducida por retrovirus. Los retrovirus aviarios pertenecen a la familia Retroviridae y el género Alpharetrovirus. Los coronavirus pueden causar enfermedades respiratorias y entéricas en varias especies de aves. Ellos pertenecen a la familia Coronaviridae y a los grupos 3a y 3c. En este estudio, se describe la presencia del virus en cuatro búhos, dos lechuzas (Tyto alba) y dos búhos de orejas (Rhinoptynx clamator), rescatados de las calles arboladas de São Paulo, Brasil y enviados al Centro de Recuperación de Animales Silvestres del Parque Ecológico de Tietê, donde hubo murieron los animales. Fragmentos de pulmón, delhígado y del intestino delgado de estas aves fueron procesados para microscopía electrónica de transmisión utilizando tinción negativa (preparación rápida), inmunomicroscopía y técnicas de inmunocitoquímica. Bajo microscopía electrónica de transmisión, partículas de paramixovirus, pleomórficas, aproximadamente esféricas o filamentosas, de 100 a 500 nm de diámetro con un sobre cubierto por espigas, y nucleocápside helicoidal con características de espiga, midiendo 15 a 20 nm de diámetro, fueron visualizadas en las muestras de pulmón, hígado e intestino delgado de todos los búhos. En muestras de intestino delgado de dos búho de orejas (búhos 3 y 4) se detectaron partículas pleomórficas con coronavirus de un diámetro de 75-160 nm con un sobre con forma de corona solar, con proyecciones de aproximadamente 20 nm de diámetro. En el hígado de un búho de orejas (búho 4) se observaron partículas pleomórficas de retrovirus con ...

Reemergence of mumps / 소아과

The mumps virus is a single-stranded, non-segmented, negative-sense RNA virus belonging to the Paramyxoviridae family. Mumps is characterized by bilateral or unilateral swelling of the parotid gland. Aseptic meningitis is a common complication, and orchitis is also common in adolescents and adult men. Diagnosis is based on clinical findings, but because of high vaccination coverage, clinical findings alone are not sufficient for diagnosis, and laboratory confirmation is needed. Mumps is preventable by vaccination, but despite high vaccination coverage, epidemics occur in several countries, including Korea. Many hypotheses are suggested for these phenomena. In this review, we investigate the reason for the epidemics, optimal methods of diagnosis, and surveillance of immunization status for the prevention of future epidemics.

Complete genome sequence analysis of a newly isolated paramyxovirus Tianjin strain / 病毒学报

Paramyxovirus Tianjin strain is the high-pathogenic virus to primate and might also cause human lower respiratory tract infection. To determine the genome structure, variation features and phylogenetic position, the complete nucleotide sequence of paramyxovirus Tianjin strain was analyzed. The homology comparison and phylogenetic analysis of the nucleotide and the deduced amino acid sequences among paramyxovirus Tianjin strain and the 28 strains in seven genera and the 7 unclassified viruses of Paramyxoviridae were performed. The results suggested that Tianjin strain is a member of the Respirovirus genus in the Paramyxovirinae, Paramyxoviridae and has the closest relationship to Sendai virus. Its genome length and composition are similar to the previously published Sendai virus except one extra glutamic acid residue increasing at the C terminus of Large protein due to the genomic RNA mutation at position A15240C. 440 unique nucleotide variations of Tianjin strain lead to 110 amino acid residue changes, making it differed from any other Sendai viruses. The phylogenetic analysis reveals paramyxovirus Tianjin strain doesn't belong to any of the three known evolution lineages of Sendai viruses and locates at a separate evolution branch. The obvious distinctions of genome nucleotide sequence, host tropism and pathogenicity suggest that paramyxovirus Tianjin strain might represent a novel genotype of Sendai virus.

Viral etiology of pneumonia in children / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To evaluate the viral pathogen of pneumonia in children.</p><p><b>METHODS</b>A total of 13 642 cases of children pneumonia in 3 years were enrolled in this study. Antigens of viral pathogen in respiratory excretion, including respiratory syncytial virus (RSV), type 1, 2 and 3 parainfluenza virus, type A and B influenza virus, and adenovirus were detected by direct immunofluorescence method.</p><p><b>RESULTS</b>Viral pneumonia accounted for 34.3% of all cases, including 25.8% cases of RSV, 4.7% of parainfluenza virus, 2.4% of type A influenza virus, 0.2% of type B influenza virus and 1.3% of adenovirus. Coinfection was found in 20 cases, in which 17 cases (85%) were infected with RSV and another virus. Positive rates of RSV in children < or = 1 year, 1 to 3 years, and >3 years were 33.1%, 19.7% and 5.1% with a significant difference (chi(2)(trend)=763.4, P < 0.001). The positive rate of adenovirus in children < or =1 year (0.7%) was significantly lower than that in children aged 1 to 3 years and in children >3 years (2.3% and 2.5%) (all P<0.01). The positive rate of type A influenza virus in children aged 1 to 3 years was higher than that in children < or =1 year (chi(2)=18.2, P<0.01). Type 1 parainfluenza virus was found in 1.2% children aged 1 to 3 years with most prevalence (P<0.05). Infection rates of type 3 parainfluenza in children < or =1 year, 1 to 3 years, and >3 years were 4.7%, 3.2% and 1.4% respectively with a significant difference (chi(2)(trend)=52.4, P<0.01). Although there were some differences of infection rate of RSV in different years, it tended to increase from November to next April with a highest rate of 62.8%. Type 3 parainfluenza virus and Type A influenza virus were almost sporadic while type A influenza virus was epidemic in August 2003 with an infection rate of 15.7%.</p><p><b>CONCLUSION</b>The highest infection rate of viral pathogen of pneumonia in children is RSV and the follows are parainfluenza, influenza and adenovirus in turn.</p>

Effects of Mumps Virus Nucleocapsid Protein on the Viral Replication and Apoptosis in VeroE6 Cells

Apoptosis, as a part of the natural defense mechanisms that protect against viral infection, plays a vital role in the pathogenic mechanisms. It also plays a key role in the pathogenesis of diseases including many viral diseases. Mechanisms of virus-induced apoptosis are not completely understood because of the complexity of the underlying biochemical cascades and all of the participating host factors. Mumps virus belongs to the genus Rubulavirus in the family Paramyxoviridae. It contains single stranded RNA genome with negative polarity. It was observed that mumps virus induced apoptosis in VeroE6 cells, and adsorption and penetration of mumps virus to cell membrane alone were not sufficient for the induction of cell death. When mumps virus was superinfected onto nucleocapsid protein (NP) expressing VeroE6 cells, cell viability and facterial titer were maintained until 13 and 12 day, respectively. The levels of p53, Bax, and Bcl-2 were increased in NP-expressing VeroE6 cells, and the increase in Bax, and Bcl-2 was outstanding. It was observed that NP protein did not directly affect the efficiency of the infection of mumps virus in NP-expressing VeroE6 cells. The levels of p53, and Bax were decreased in both mock-infected VeroE6 cells and NP-expressing VeroE6 cells infected with mumps virus. However, the Bcl-2 level was little affected by the virus infection.

Production and Characterization of Monoclonal Antibodies to Mumps Virus Isolated in Korea

Classical mumps patients develop bilateral or less commonly unilateral parotitis. Mumps virus belongs to the genus Rubulavirus in the family Paramyxoviridae. It contains single stranded RNA genome with negative polarity. To characterize the antigenicity of mumps virus isolated in Korea, nineteen hybridoma cell lines producing monoclonal antibodies to mumps virus were established by fusion of Sp2/0-Ag14 mouse myeloma cells with spleen cells of mice immunized with mumps virus strain 98-40. The specificity of these monoclonal antibodies was established by immunofluorescence microscopy and immunoblotting analysis. Fifteen out of nineteen hybridoma cell lines secreted IgG monoclonal antibodies (MAbs) against mumps virus, and the remaining four secreted IgM. The isotypes of thirteen clones of 19 MAbs were IgG1, two were IgG2a, and four were IgM. Eight MAbs reacted with a 68 kDa nucleocapsid protein, six MAbs reacted with a 46 kDa phosphoprotein, and five MAbs reacted with a 42 kDa matrix protein.

Isolation of an Ophidian Paramyxovirus in a captive rattlesnake (Crotalus durissus terrificus) from Botucatu, Säo Paulo State, Brazil

This study reports the isolation of an Ophidian Paramyxovirus (OPMV) in sputum of a captive rattlesnake (Crotalus durissus terrificus) kept in a serpentarium located in Botucatu, Säo Paulo State, Brazil. Polymerase chain reaction (PCR) and nested-PCR were performed for the identification of the isolated virus.

Rapid Detection and Identification of Human Respiratory Syncytial Virus, Human Parainfluenza Virus Type 1, 2 and 3 by Single-tube Multiplex Reverse Transcription Polymerase Chain Reaction

Laboratory diagnosis of respiratory viral infection has traditionally been based upon virus isolation and/or viral antigen identification. Recently, more sensitive and specific nucleic acid detection methods by reverse transcription- polymerase chain reaction (RT-PCR) have been developed, however, conventional RT-PCR can identify only a single suspected virus. To identify the causative agents which belong to Paramyxoviridae of respiratory virus infections, we have developed a single-tube multiplex RT-PCR using four primer sets which can amplify respiratory syncytial virus and parainfluenza virus type 1, 2 and 3 simultaneously. Assay sensitivity of single-tube multiplex RT-PCR allowed a detection in the range of 3~500 TCID50 and there were no cross amplification among other respiratory viral agents based on the test using reference virus stocks. The single-tube multiplex RT-PCR was able to directly detect viruses in respiratory specimens, with virus being detected 11 of 80 samples as compared to 9 of 80 samples detected by indirect immunofluorescence or antigen detection following shell vial culture. This result suggests that the single-tube multiplex RT-PCR can be established as a more sensitive and rapid diagnostic application than shell vial assay for the detection of respiratory infection of Paramyxoviridae.

Prevalence of parainfluenza and influenza viruses amongst children with upper respiratory tract infection

The objective of this study was to determine the prevalence of Parainfluenza and Influenza causing upper respiratory tract infections and to evaluate shell vial culture assay and direct immunofluorescence assay. A retrospective study during the period between November 1997 and May 1998. A total of 350 nasopharyngeal aspirates were obtained from children suffering from respiratory tract infections. Nasopharyngeal aspirates were investigated for the presence of Parainfluenza 1, 2 and 3, Influenza A and B using shell vial culture assay, conventional culture assay and direct immunofluorescence assay. Parainfluenza 1 were identified in 3%, Parainfluenza 2 in 5% and Parainfluenza 3 in 6%. Influenza A were identified in 4% and Influenza B in 2%. Parainfluenza 1, 2 and 3 were isolated in children less than 5 years old. Most of Parainfluenza cases were associated with other upper respiratory infections. Shell vial assay showed a sensitivity of 90-93% and specificity of 99-100% for detecting Parainfluenza 1, 2 and 3. These results emphasize that shell vial assay is important for the diagnosis of Parainfluenza and Influenza, although direct immunofluorescence assay is the superior diagnositic assay

Vigilancia sistemática de virus influenza, respiratorio sincicial, parainfluenza y adenovirus en niños ambulatorios con infecciones respiratorias agudas / Systematic surveillance of influenza, syncytial respiratory, parainfluenza and adenovirus in ambulatory children with acute respiratory infections

Background: The efficacy of influenza vaccination programs depends on the antigenic similitude between vaccine and the influenza virus circulating in the community. Therefore the surveillance of clinical activity and antigenic features of influenza virus is of utmost importance. Aim: To perform a systematic surveillance of clinical activity and antigenic characteristics of influenza virus. Material and methods: Since 1996 and during the cold months (may to september), 20 samples of upper respiratory secretions per week, were obtained from children with acute respiratory infections consulting to the emergency room of a public hospital. Using indirect immunofluorescence and cellular cultures, the presence of influenza, syncytial respiratory, parainfluenza and adenovirus was assessed. The weekly number of consultations in the emergency room and the number of hospital discharges due to acute respiratory infections, were registered. Results: Influenza and syncytial respiratory were the predominant virus detected since 1996. In 1996 and 1998, the weekly detection of influenza virus followed a single seasonal curve. The maximal weekly positively results reached 85 and 80 percent of the obtained samples, respectively. During 1997, two curves of influenza virus activity were observed, but none reached more than 50 percent of weekly positive samples. The demand for outpatient care evolved in parallel to the weekly detection of influenza virus. The hospital discharges due to acute respiratory infections paralleled the syncytial respiratory virus detection rates. Conclusions: This surveillance model is effective for the detection of influenza and other virus responsible for acute respiratory infections and their relationship with the demand for health care during the cold months

Influencia de virus respiratorios, frío y contaminación aérea en la infección respiratoria aguda baja del lactante / Influence of respiratory viruses, cold weather and air pollution in the incidence of lower respiratory tract infections in infants

Background: All winters, there is an increase in the number of pediatric consultations, associated to three factors: cold weather, air pollution and respiratory virus epidemics. Aim: To study the influence of these three factors in the demand for pediatric consultations between march and september, in an area of Metropolitan Santiago. Patients and Methods: The number of consultations between march and september 1998 in the emergency room and the number of hospital discharges due to lower respiratory tract infections, were registered in a public pediatric hospital of Santiago. A respiratory virus surveillance (respiratory syncytial virus, adenovirus, influenza and parainfluenza virus) was done among children admitted for lower respiratory infections. Atmospheric temperature values and air pollution, measured as the number of particles of 10 µm or more per m3 (MP 10), were obtained from local health services. Results: Two elevation waves of outpatient consultations were detected at weeks 19 and 26, that coincided with the periods of maximal detection of influenza and syncytial respiratory virus, respectively. The epidemics of respiratory syncytial virus coincided with the maximal number of hospital admissions for lower respiratory tract infections at week 27. There was no correlation between air pollution and the number of pediatric consultations. The lower ambient temperatures coincided with the higher detection of respiratory syncytial virus at week 28, moment in which the demand for consultations or hospital admissions was descending. Conclusions: There is a direct relationship between respiratory virus epidemics and the demand for pediatric consultations. There is also a minor influence of ambient temperature

Padrões de circulação temporal em vírus sincicial respiratório humano dos grupos A e B / Standards of temporal circulatory in human respiratory syncytial virus in groups A e B

O vírus respiratório síncicial humano é classificado em dois grupos principais, A e B. Ambos os grupos contêm múltiplas variantes, reconhecidas por anticorpos monoclonais e técnicas genéticas, notadamente sequenciamento. Com o intuito de caracterizar a epidemiologia molecular de cepas de vírus respiratório sincicial humano, foi realizado o sequenciamento de uma região variável do gene que codifica a proteína responsável pela ligação do respectivo vírus à célula em amostras colhidas durante 5 anos consecutivos em uma comunidade. A análise filogenética realizada identificou clades distintas (genotipos), subsequentemente divididos em subtipos, com base em similiaridade > 96 por cento a nível de nucleotídeo. Foram identificados cinco genotipos e 22 subtipos entre os 123 isolados de vírus respiratório sincicial humano do grupo A e quatro genotipos e seis subtipos entre os 81 isolados do grupo B. Um ou dois genotipos e subtipos representaram no mínimo 50 por cento dos isolados identificados em cada ano. Foi verificada uma altemância no genotipo e subtipo predominantes, circulantes em cada ano, sendo que nenhum genotipo ou subtipo predominou por mais de um ano nos cinco anos do estudo. A consistência na substituição das cepas predominantes sugere que um "shift", mesmo entre as cepas de um mesmo grupo, representaria uma vantagem evolutiva para o vírus. Postulamos que a "nova" cepa circulante em um determinado ano teria maior capacidade de evadir a imunidade previamente induzida a nível da população e consequentemente circular mais eficientemente. A altemância anual apresentada pelas cepas de vírus respiratório sincicial humano pode contribuir para a melhor capacidade do vírus em causar surtos anuais de doença respiratória. Nossos resultados também sugerem que a caracterização de vírus respiratório sincicial humano a nível de grupo e genotipo pode ser necessária para compreender melhor o papel da imunidade protetora, após a infecção natural pelo vírus, bem como para a avaliação dos estudos envolvendo a eficácia de vacinas contra o vírus

Neumonitis inducida por el rubulavirus porcino / Pneumonitis induced by pork rubulavirus

Introducción: El rubulavirus porcino es un virus miembro de la familia Paramixoviridae, subfamilia paramixovirinae y género Rubulavirus. Este virus posee gran homología en la secuencia de nucleótidos y aminoácidos con los virus de las paperas, virus símicos y virus de la parinfluenza 2 y 4. El rubulavirus porcino es responsable de la enfermedad del ojo azul que afecta a cerdos de todas las edades y provoca alteraciones reproductivas, neurológicas y respiratorias. Objetivo: En el presente trabajo identificamos las principales lesiones pulmonares que provoca la infección experimental de cerdos con el rubulavirus porcino. Materiales y métodos: Los animales fueron inoculados por vía intranasal y sacrificados en diferentes tiempos postinfección. En cada tiempo postinfección se analizaron las lesiones macroscópicas y microscópicas, se determinó el título de anticuerpos, y se realizó el aislamiento viral de diversos tejidos. Resultados: Se demostró que el rubulavirus porcino induce una neumonitis intersticial con un infiltrado mononuclear, características de infecciones ocasionadas por paramoxovirus como el virus de las paperas o el virus del sarampión. El aislamiento viral fue mayor en el día cinco postinfección, de manera interesante se logró recuperar el virus principalmente en la tonsila, tráquea y pulmón. Discusión: Con base en estos resultados, este artículo propone a este virus como un modelo experimental para estudiar la patología y respuesta inmune en infecciones causadas por paramixovirus