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...

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.

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

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

Evaluation of WHO monoclonal antibody kit for diagnosis of acute respiratory viral infections.

In 1990 and 1991, six laboratories located in the WHO Western Pacific Region (WPR) and South East Asian Region (SEAR) were selected, based on their experience in the immunofluorescence antibody technique (IFAT), to participate in the evaluation of a WHO monoclonal antibody (Mab) kit to detect respiratory syncytial (RS) virus, influenza A virus, influenza B virus, parainfluenza virus and adenovirus. Despite differences in the initial standardization procedures, the WHO monoclonal antibodies were found to be of high quality, sensitivity and specificity when tested on clinical specimens. The constant supply of affordable high quality reagents from WHO would enable their use in clinical virological laboratories in the developing countries as well as promote the utilization of IFAT as an adjunct to cell culture isolation in the diagnosis of acute respiratory viral infections.