Effects of neutrophil extracellular traps during human respiratory syncytial virus infection in vitro / Efeitos das redes extracelulares dos neutrófilos durante a infecção in vitro pelo vírus sincicial respiratório

Abstract The human respiratory syncytial virus (hRSV) is the most common cause of severe lower respiratory tract diseases in young children worldwide, leading to a high number of hospitalizations and significant expenditures for health systems. Neutrophils are massively recruited to the lung tissue of patients with acute respiratory diseases. At the infection site, they release neutrophil extracellular traps (NETs) that can capture and/or inactivate different types of microorganisms, including viruses. Evidence has shown that the accumulation of NETs results in direct cytotoxic effects on endothelial and epithelial cells. Neutrophils stimulated by the hRSV-F protein generate NETs that are able to capture hRSV particles, thus reducing their transmission. However, the massive production of NETs obstructs the airways and increases disease severity. Therefore, further knowledge about the effects of NETs during hRSV infections is essential for the development of new specific and effective treatments. This study evaluated the effects of NETs on the previous or posterior contact with hRSV-infected Hep-2 cells. Hep-2 cells were infected with different hRSV multiplicity of infection (MOI 0.5 or 1.0), either before or after incubation with NETs (0.5-16 μg/mL). Infected and untreated cells showed decreased cellular viability and intense staining with trypan blue, which was accompanied by the formation of many large syncytia. Previous contact between NETs and cells did not result in a protective effect. Cells in monolayers showed a reduced number and area of syncytia, but cell death was similar in infected and non-treated cells. The addition of NETs to infected tissues maintained a similar virus-induced cell death rate and an increased syncytial area, indicating cytotoxic and deleterious damages. Our results corroborate previously reported findings that NETs contribute to the immunopathology developed by patients infected with hRSV.

Resumo O vírus sincicial respiratório humano (hRSV) é a causa mais comum de doenças graves do trato respiratório inferior em crianças pequenas em todo o mundo, resultando em grande número de hospitalizações e gastos significativos para os sistemas de saúde. Neutrófilos são recrutados em massa para o tecido pulmonar de pacientes com doenças respiratórias agudas. No local da infecção, eles liberam armadilhas extracelulares de neutrófilos (NETs) que podem capturar e/ou inativar diferentes tipos de microrganismos, incluindo vírus. Evidências demonstraram que o acúmulo de NETs resulta em efeitos citotóxicos diretos nas células endoteliais e epiteliais. Os neutrófilos estimulados pela proteína F do vírus sincicial respiratório (hRSV-F) geram NETs que são capazes de capturar partículas virais, reduzindo assim sua transmissão. No entanto, a produção maciça de NETs obstrui as vias aéreas e aumenta a gravidade da doença. Assim, um maior conhecimento sobre os efeitos das NETs durante as infecções por hRSV é essencial para o desenvolvimento de novos tratamentos específicos e eficazes. Este estudo avaliou os efeitos das NETs no contato prévio ou posterior à infecção de células Hep-2 com hRSV. As células Hep-2 foram infectadas com diferentes quantidades de hRSV (multiplicidade de infecção ou MOI 0,5 ou 1,0), antes ou após a incubação com NETs (0,5-16 μg/mL). Células infectadas e não tratadas mostraram redução da viabilidade celular e intensa coloração com azul de tripano, que foi acompanhada pela formação de sincícios numerosos e grandes. O contato prévio entre as NETs e as células não resultou em efeito protetor. As células em monocamadas mostraram um número e área de sincícios reduzidos, mas a morte celular foi semelhante àquela apresentada por células infectadas e não tratadas. A adição de NETs aos tecidos infectados manteve taxa de morte celular e formação de sincícios semelhantes àqueles induzidos pelo vírus em células não tratadas, indicando danos citotóxicos e deletérios. Nossos resultados corroboram achados relatados anteriormente de que as NETs contribuem para a imunopatologia desenvolvida por pacientes infectados com hRSV.

Effects of neutrophil extracellular traps during human respiratory syncytial virus infection in vitro / Efeitos das redes extracelulares dos neutrófilos durante a infecção in vitro pelo vírus sincicial respiratório

The human respiratory syncytial virus (hRSV) is the most common cause of severe lower respiratory tract diseases in young children worldwide, leading to a high number of hospitalizations and significant expenditures for health systems. Neutrophils are massively recruited to the lung tissue of patients with acute respiratory diseases. At the infection site, they release neutrophil extracellular traps (NETs) that can capture and/or inactivate different types of microorganisms, including viruses. Evidence has shown that the accumulation of NETs results in direct cytotoxic effects on endothelial and epithelial cells. Neutrophils stimulated by the hRSV-F protein generate NETs that are able to capture hRSV particles, thus reducing their transmission. However, the massive production of NETs obstructs the airways and increases disease severity. Therefore, further knowledge about the effects of NETs during hRSV infections is essential for the development of new specific and effective treatments. This study evaluated the effects of NETs on the previous or posterior contact with hRSV-infected Hep-2 cells. Hep-2 cells were infected with different hRSV multiplicity of infection (MOI 0.5 or 1.0), either before or after incubation with NETs (0.5–16 μg/mL). Infected and untreated cells showed decreased cellular viability and intense staining with trypan blue, which was accompanied by the formation of many large syncytia. Previous contact between NETs and cells did not result in a protective effect. Cells in monolayers showed a reduced number and area of syncytia, but cell death was similar in infected and non-treated cells. The addition of NETs to infected tissues maintained a similar virus-induced cell death rate and an increased syncytial area, indicating cytotoxic and deleterious damages. Our results corroborate previously reported findings that NETs contribute to the immunopathology developed by patients infected with hRSV.

O vírus sincicial respiratório humano (hRSV) é a causa mais comum de doenças graves do trato respiratório inferior em crianças pequenas em todo o mundo, resultando em grande número de hospitalizações e gastos significativos para os sistemas de saúde. Neutrófilos são recrutados em massa para o tecido pulmonar de pacientes com doenças respiratórias agudas. No local da infecção, eles liberam armadilhas extracelulares de neutrófilos (NETs) que podem capturar e/ou inativar diferentes tipos de microrganismos, incluindo vírus. Evidências demonstraram que o acúmulo de NETs resulta em efeitos citotóxicos diretos nas células endoteliais e epiteliais. Os neutrófilos estimulados pela proteína F do vírus sincicial respiratório (hRSV-F) geram NETs que são capazes de capturar partículas virais, reduzindo assim sua transmissão. No entanto, a produção maciça de NETs obstrui as vias aéreas e aumenta a gravidade da doença. Assim, um maior conhecimento sobre os efeitos das NETs durante as infecções por hRSV é essencial para o desenvolvimento de novos tratamentos específicos e eficazes. Este estudo avaliou os efeitos das NETs no contato prévio ou posterior à infecção de células Hep-2 com hRSV. As células Hep-2 foram infectadas com diferentes quantidades de hRSV (multiplicidade de infecção ou MOI 0,5 ou 1,0), antes ou após a incubação com NETs (0,5–16 μg/mL). Células infectadas e não tratadas mostraram redução da viabilidade celular e intensa coloração com azul de tripano, que foi acompanhada pela formação de sincícios numerosos e grandes. O contato prévio entre as NETs e as células não resultou em efeito protetor. As células em monocamadas mostraram um número e área de sincícios reduzidos, mas a morte celular foi semelhante àquela apresentada por células infectadas e não tratadas. A adição de NETs aos tecidos infectados manteve taxa de morte celular e formação de sincícios [...].

Vigilancia de virus sincicial respiratorio e influenza en niños escolarizados asistidos en un hospital pediátrico durante 2 meses del segundo semestre de 2021 / Respiratory syncytial virus and influenza surveillance in schoolchildren seen at a children's hospital over 2 months of the second semester of 2021

Introducción. Durante la pandemia de COVID-19, disminuyeron las notificaciones de infecciones respiratorias. El objetivo fue estimar la prevalencia de virus sincicial respiratorio (VSR) e influenza en niños escolarizados asistidos en un hospital pediátrico durante el retorno a la presencialidad. Métodos. Estudio transversal de casos sospechosos de COVID-19, de 3-18 años, con prueba negativa para SARSCoV-2, entre agosto y octubre de 2021. Se estratificó por nivel educativo. Se utilizó PCR para detectar VSR e influenza. Resultados. Se incluyeron 619 niños: 234 del nivel inicial, 224 del primario y 161 del secundario; 25,5 % (158) fueron positivos para VSR (36,3 % del nivel inicial versus 21 % del primario y 16 % del secundario); en adolescentes se asoció la infección al contacto escolar con caso sintomático (OR 2,5; IC95%: 1-6,80; p = 0,04). No se aisló virus influenza. Conclusión. VSR se aisló en un cuarto de la población estudiada, con mayor frecuencia en el nivel inicial; en adolescentes, se asoció con contacto escolar sintomático. No se detectaron casos de influenza

Introduction. Reporting of respiratory infections reduced during the COVID-19 pandemic. The objective was to estimate the prevalence of respiratory syncytial virus (RSV) and influenza in schoolchildren seen at a children's hospital during the return to school. Methods. Cross-sectional study of patients aged 3­18 years suspected of COVID-19 with a negative test for SARS-CoV-2 between August and October 2021. Participants were stratified by level of education. PCR was used to detect RSV and influenza. Results. A total of 619 children were included: 234 in preschool, 224 in primary and 161 in secondary school; 25.5% (158) tested positive for RS (36.3% in the pre-school level versus 21% in primary and 16% in secondary school). Infection among adolescents was associated with school contact with symptomatic cases (OR 2.5; 95%CI 1­6.80; p = 0.04). No case of influenza was detected. Conclusion. RSV was isolated in one fourth of the study population, with a higher frequency in pre-school; among adolescents, it was associated with school contact with symptomatic cases. No case of influenza was detected.

Asociación temporal entre la circulación de virus respiratorios y hospitalizaciones por enfermedad de Kawasaki / Temporal association between the circulation of respiratory viruses and hospitalizations due to Kawasaki disease

INTRODUCCIÓN: La etiología de la enfermedad de Kawasaki (EK) es desconocida, planteándose que infecciones virales la gatillan en pacientes susceptibles. OBJETIVO: Estudiar la asociación temporal entre la circulación de virus respiratorios y hospitalizaciones por EK en la Región Metropolitana (RM), Chile, entre 2010-2017. METODOLOGÍA: Estudio ecológico retrospectivo de casos de EK en pacientes bajo 18 años de edad, en base a egresos hospitalarios. La circulación de virus se analizó mediante el reporte de la red de vigilancia metropolitana. Se utilizaron promedios móviles para EK (PMEK) y virus respiratorios (PMVR). RESULTADOS: Se registraron 14.902 casos de infecciones virales respiratorias entre 2010-2017. Se observó correlación directa entre PMVR-virus respiratorio sincicial (VRS) de un mes y año y PMEK del mes subsiguiente (coeficiente de correlación (ρ) = +0,441; p < 0,001), y una asociación similar para PMVR-influenza A (FLU A) (ρ = +0,362; p < 0,001). PMVR-influenza B (FLU B) y PMVR-metapneumovirus (MPV) presentan correlaciones directas con PMEK (ρ = +0,443; p < 0,001 y ρ = +0,412; p < 0,001, respectivamente), siendo contemporáneo en mes y año con EK para FLU B, mientras que MPV presenta un desfase de un mes entre PMVR y PMEK. CONCLUSIÓN: Existe correlación temporal directa entre la circulación de VRS, FLU A, FLU B y MPV con EK en niños de la RM, Chile.

BACKGROUND: The etiology of Kawasaki disease (KD) is unknown. It is believed that viral infections could trigger the disease in susceptible patients. AIM: To study the temporal association between the circulation of respiratory viruses and KD hospitalizations in the Metropolitan Region (MR), Chile, between 2010-2017. METHODS: Ecologic study consisting of a review of KD cases in children under 18 years of age based on hospital discharges. The circulation of respiratory viruses was analyzed using the report of the metropolitan surveillance network. Moving averages for KD (MAKD) and respiratory viruses (MARV) were used. RESULTS: 14,902 cases of respiratory virus infections were recorded between 2010-2017. A direct correlation was found between MARV-respiratory syncytial virus (RSV) of one month and year and MAKD of the subsequent month (correlation coefficient (ρ) = +0.441; p < 0.001). A similar association was found for MARV-influenza A (FLU A) (ρ = + 0.362; p < 0.001). MARV-influenza B (FLU B) and MARV-metapneumovirus (MPV) had direct correlations with MAKD (ρ = +0.443; p < 0.001 and ρ = +0.412; p < 0.001, respectively), being FLU B contemporary in month and year with KD, and MPV presenting a one-month lag. CONCLUSION: There is a direct temporal correlation between RSV, FLU A, FLU B and MPV circulation and KD in children from RM, Chile.

Letalidad en lactantes con cardiopatías congénitas hospitalizados por virus respiratorio sincicial / Case fatality in infants with congenital heart disease hospitalized for respiratory syncytial virus

INTRODUCCIÓN. Las cardiopatías congénitas son un factor de riesgo para desarrollar enfermedad severa por virus respiratorio sincicial (VRS). En Chile no se conoce la hospitalización o letalidad por esta causa. El objetivo de este estudio fue determinar la letalidad de niños menores de 2 años con cardiopatías congénitas hospitalizados por infección por VRS en el hospital de niños Roberto del Río, Santiago, Chile. MÉTODO. Estudio descriptivo retrospectivo de revisión de fichas clínicas de niños menores de 24 meses con cardiopatía congénita, hospitalizados por infección respiratoria baja por VRS. Se registró edad, género, tipo de cardiopatía congénita, comorbilidades, días de hospitalización, ingreso a unidad de paciente crítico y letalidad en Hospital Roberto del Río durante los años 2014 a 2016. Se analizaron resultados mediante Stata 13. Aprobado por Comité de ética del Servicio de Salud Metropolitano Norte RESULTADOS: Se estudian 94 pacientes hospitalizados, mediana de edad de 7,3 meses, 45 (48%) hombres. Los casos de cardiopatía congénita cianótica fueron 7 (7,4%), obstructivas izquierdas 3 (3,2%) y no obstructivas 84 (89,3%). Las comorbilidades fueron: 17 (18,08%) trisomía 21, 10 (10,6%) patología neurológica, 6 (6,38%) reflujo gastroesofágico. Sin comorbilidad 48 pacientes (51,06%). La mediana de hospitalización es 8 días y la necesidad de ventilación mecánica de 1 día, siendo mayor en las cianóticas. Requieren ingreso a unidad de paciente crítico 49 (52,12%). La letalidad fue de un 8,5%. CONCLUSIÓN: La morbimortalidad de la infección por VRS observada en pacientes con cardiópatas congénitas es elevada, por lo que la prevención con anticuerpos monoclonales podría tener impacto. En el 2019 Chile implementa el uso de anticuerpos monoclonales anti VRS en niños con cardiopatías congénitas por lo que será interesante medir el impacto de esta medida.

INTRODUCTION. Congenital heart disease is a risk factor for developing severe disease due to respiratory syncytial virus (RSV). In Chile the rate of hospitalization or lethality due to this cause is not known. The objective of this study was to determine lethality of infants with congenital heart disease hospitalized for RSV infection. METHOD. Retrospective descriptive study, through review of clinical records of infants under 24 months with congenital heart disease, hospitalized due to low RSV respiratory infection. We recorded age, gender, type of congenital heart disease, comorbidities, days of hospitalization, admission to a critical patient unit and lethality in Roberto del Río Hospital between 2014 to 2016. The research had approved bay the ethical Comitee Servicio de Salud Metropolitano Norte. Results were analyzed through Stata 13. RESULTS. 94 hospitalized patients were studied, median age of 7.3 months, 45 (48%) men. The cases of congenital cyanotic heart disease were 7 (7.4%), left obstructive 3 (3.2%) and non-obstructive 84 (89.3%). The comorbidities were: 17 (18.08%) trisomy 21, 10 (10.6%) neurological pathology, 6 (6.38%) gastroesophageal reflux and 48 patients (51.06%) did not present. The hospitalization median is 8 days and the need for 1-day mechanical ventilation is greater in cyanotic patients. They require admission to the critical patient unit 49 (52.12%). The lethality is 8.5%. CONCLUSION: The lethality of RSV infection observed in patients with congenital heart disease is high. In 2019 Chile implemented the use of RSV monoclonal antibodies congenital heart disease. New studies are needed to measure the impact of this new policy. Keywords: congenital heart disease, respiratory syncytial virus

Differential proteomic analysis of children infected with respiratory syncytial virus

Respiratory syncytial virus (RSV) infection is the main cause of lower respiratory tract infection in children. However, there is no effective treatment for RSV infection. Here, we aimed to identify potential biomarkers to aid in the treatment of RSV infection. Children in the acute and convalescence phases of RSV infection were recruited and proteomic analysis was performed to identify differentially expressed proteins (DEPs). Subsequently, promising candidate proteins were determined by functional enrichment and protein-protein interaction network analysis, and underwent further validation by western blot both in clinical and mouse model samples. Among the 79 DEPs identified in RSV patient samples, 4 proteins (BPGM, TPI1, PRDX2, and CFL1) were confirmed to be significantly upregulated during RSV infection. Functional analysis showed that BPGM and TPI1 were mainly involved in glycolysis, indicating an association between RSV infection and the glycolysis metabolic pathway. Our findings provide insights into the proteomic profile during RSV infection and indicated that BPGM, TPI1, PRDX2, and CFL1 may be potential therapeutic biomarkers or targets for the treatment of RSV infection.

Risk factors for recurrent wheezing in preterm infants who received prophylaxis with palivizumab / Fatores de risco para sibilância recorrente em crianças pré-termo que receberam profilaxia com palivizumabe

ABSTRACT Objective: To determine the prevalence of recurrent wheezing (RW) in preterm infants who received prophylaxis against severe infection with respiratory syncytial virus (RSV) and to identify genetic susceptibility (atopy or asthma) and risk factors for RW. Methods: This was a cross-sectional study involving preterm infants who received prophylaxis with palivizumab at a referral center in Brazil during the first two years of age. A structured questionnaire was administered in a face-to-face interview with parents or legal guardians. Results: The study included 410 preterm infants (median age = 9 months [0-24 months]). In the sample as a whole, 111 children (27.1%; [95% CI, 22.9-31.5]) had RW. The univariate analysis between the groups with and without RW showed no differences regarding the following variables: sex, ethnicity, maternal level of education, gestational age, birth weight, breastfeeding, number of children in the household, day care center attendance, pets in the household, and smoking caregiver. The prevalence of RW was twice as high among children with bronchopulmonary dysplasia (adjusted OR = 2.08; 95% CI, 1.11-3.89; p = 0.022) and almost five times as high among those with a personal/family history of atopy (adjusted OR = 4.96; 95% CI, 2.62-9.39; p < 0.001) as among those without these conditions. Conclusions: Preterm infants who received prophylaxis with palivizumab but have a personal/family history of atopy or bronchopulmonary dysplasia are more likely to have RW than do those without these conditions.

RESUMO Objetivo: Determinar a prevalência de sibilância recorrente (SR) em crianças pré-termo que receberam profilaxia contra infecção grave pelo vírus sincicial respiratório (VSR) e identificar susceptibilidade genética (atopia ou asma) e fatores de risco para SR. Métodos: Estudo transversal envolvendo crianças pré-termo que receberam profilaxia com palivizumabe em um centro de referência no Brasil durante os primeiros dois anos de vida. Um questionário estruturado foi aplicado em entrevista presencial com os pais ou responsáveis. Resultados: O estudo incluiu 410 crianças pré-termo (mediana de idade = 9 meses [0-24 meses]). Na amostra total, 111 crianças (27,1%; IC95%: 22,9-31,5) apresentavam SR. A análise univariada entre os grupos com e sem SR não mostrou diferenças em relação às seguintes variáveis: sexo, etnia, escolaridade materna, idade gestacional, peso ao nascer, aleitamento materno, número de crianças no domicílio, frequência em creche, presença de animais de estimação no domicílio e cuidador tabagista. A prevalência de SR foi duas vezes maior entre crianças com displasia broncopulmonar (OR ajustada = 2,08; IC95%: 1,11-3,89; p = 0,022) e quase cinco vezes maior entre aquelas com história pessoal/familiar de atopia (OR ajustada = 4,96; IC95%: 2,62-9,39; p < 0,001) do que entre aquelas sem essas condições. Conclusões: Crianças pré-termo que receberam profilaxia com palivizumabe, mas apresentam história pessoal/familiar de atopia ou displasia broncopulmonar, têm maior probabilidade de apresentar SR do que aquelas sem essas condições.

Priorización de nuevas vacunas e innovación al servicio de estrategias de vacunación / New vaccines prioritization and immunization-related innovation

La vacunación es el medio más efectivo para controlar la morbilidad y mortalidad relacionadas con enfermedades infecciosas. Para lograr esto, necesitamos vacunas inmunogénicas y seguras que faciliten y mejoren sus condiciones de transporte, almacenamiento y administración. Gracias a los avances en inmunología y bioinformática, es posible impulsar el descubrimiento de nuevas vacunas para enfrentar la tuberculosis, el virus respiratorio sincicial, el Streptococcus agalactiae, la enfermedad meningocócica invasora, entre otros. Así también, nuevas tecnologías, como la producción de vacunas utilizando plantas transgénicas y parches de microagujas, los cuales podrían facilitar la producción, disminuir los costos y efectos adversos. Sin embargo, no solo necesitamos las vacunas, sino que debemos conocer la epidemiología de las enfermedades prevenibles con vacuna para tomar decisiones fundadas, con el objetivo de planificar estrategias sanitarias, medir su impacto y evaluar la seguridad de su utilización, para alcanzar las metas de salud pública y la confianza de la población.

Vaccination is the most effective strategy to avoid morbidity and mortality related to infectious diseases. To achieve this, we need immunogenic and safe vaccines that facilitate and improve its transport, storage and administration conditions. Thanks to current advances in immunology and bioinformatics, it is possible to boost the discovery of new vaccines to deal with tuberculosis, the respiratory syncytial virus, Streptococcus agalactiae, meningococcal invasive disease, among others. In addition to new technologies such as the production of plant-based vaccines, and microneedles patches, which can facilitate its production, reducing costs and adverse effects. However, vaccines is not the only thing that we need, because we must know the epidemiology and burden of disease to take informed decisions to design optimal strategies, measuring their impact and assessing the safety of their use in order to achieve the goals health and population confidence.

First report of two consecutive respiratory syncytial virus outbreaks by the novel genotypes ON-1 and NA-2 in a neonatal intensive care unit / Primeiro relato de dois surtos consecutivos de vírus sincicial respiratório pelos novos genótipos ON-1 e NA-2 em uma unidade de terapia intensiva neonatal

Abstract Objective: Respiratory syncytial virus is a pathogen frequently involved in nosocomial outbreaks. Although several studies have reported nosocomial outbreaks in neonatal intensive care units, molecular epidemiology data are scarce. Here, the authors describe two consecutive respiratory syncytial virus outbreaks caused by genotypes ON-1 and NA-2 in a neonatal intensive care unit in São Paulo, Brazil. Methods: A prospective search for respiratory syncytial virus was performed after diagnosing the index case and four other symptomatic newborns in the neonatal intensive care unit. Nasopharyngeal aspirate samples of all patients in the neonatal intensive care unit were tested for 17 respiratory viruses using real-time reverse transcriptase polymerase chain reaction. Genotyping was performed using nucleotide sequencing. Results: From May to August 2013, two different outbreaks were detected in the neonatal intensive care unit. A total of 20 infants were infected with respiratory syncytial virus-A (ten and 14 with ON-1 and NA-2 genotypes, respectively). The mean age of the infants was 10 days, mean birth weight was 1,961 g, and the mean gestational age was 33 weeks. Risk factors (heart disease, lung disease, and prematurity) were present in 80% and 85.7% of infants in the ON-1 and NA-2 groups, respectively. In total, 45.8% of infants were asymptomatic and 20.8% required mechanical ventilation. Coinfections were not detected during the outbreaks. Conclusions: Infants in a neonatal intensive care unit who develop abrupt respiratory symptoms should be tested for respiratory viruses, especially respiratory syncytial virus. Even in the absence of severe symptoms, respiratory syncytial virus detection can prevent nosocomial transmission through infection control measures. A better understanding of respiratory syncytial virus molecular epidemiology is essential for developing new vaccines and antiviral drugs against respiratory syncytial virus.

Resumo Objetivo O vírus sincicial respiratório é um patógeno frequentemente envolvido em surtos nosocomiais. Embora vários estudos tenham relatado tais surtos em unidades de terapia intensiva neonatal, os dados epidemiológicos moleculares são escassos. Neste artigo, descrevemos dois surtos consecutivos de vírus sincicial respiratório causados pelos genótipos ON-1 e NA-2 em uma unidade de terapia intensiva neonatal em São Paulo, Brasil. Métodos Uma busca prospectiva por vírus sincicial respiratório foi realizada após o diagnóstico do caso índice e outros quatro recém-nascidos sintomáticos na unidade de terapia intensiva neonatal. Amostras de aspirado nasofaríngeo de todos os pacientes da unidade de terapia intensiva neonatal foram testadas para 17 vírus respiratórios com reação em cadeia da polimerase via transcriptase reversa em tempo real. A genotipagem realizada utilizando sequenciamento de nucleotídeos. Resultados De maio a agosto de 2013, foram detectados dois surtos diferentes na unidade de terapia intensiva neonatal. Vinte e quatro crianças foram infectadas com vírus sincicial respiratório-A (10 e 14 com os genótipos ON-1 e NA-2, respectivamente). A média da idade dos lactentes era de 10 dias, o peso médio ao nascer foi de 1961 g e a idade gestacional média de 33 semanas. Fatores de risco (doença cardíaca, doença pulmonar e prematuridade) estavam presentes em 80% e 85,7% dos bebês nos grupos ON-1 e NA-2, respectivamente. No total, 45,8% dos lactentes eram assintomáticos e 20,8% necessitaram de ventilação mecânica. Não foram detectadas coinfecções durante os surtos. Conclusões Bebês em unidade de terapia intensiva neonatal que desenvolvem sintomas respiratórios abruptos devem ser testados para vírus respiratórios, especialmente o vírus sincicial respiratório. Mesmo na ausência de sintomas graves, a detecção de vírus sincicial respiratório pode prevenir a transmissão nosocomial através de medidas de controle de infecção. Um melhor entendimento da epidemiologia molecular do vírus sincicial respiratório é essencial para o desenvolvimento de novas vacinas e drogas antivirais contra o vírus sincicial respiratório.

Bronquiolitis aguda: tratamiento de la insuficiencia respiratoria / Acute bronchiolitis: treatment of respiratory insufficiency

The severe respiratory insufficiency (SRI) caused by acute bronchitis whose main etiology is the respiratory syncytial virus is the main cause of under 2-year-old children hospitalization during the winter months, especially in the risk groups. Its treatment is mainly based in general measures, administration of respiratory support with standard oxygen therapy, non-invasive ventilation, invasive mechanical ventilation or the emerging high flow nasal cannula therapy, which these past few years has become an easy alternative of use, well tolerated, secure to be used in emergency rooms, basic rooms and pediatric intensive care units. The election of therapy will depend of the patient severity, the level of complexity of the healthcare center and the experience in the different treatment modalities of the health team. It is essential to carry out protocols and guidelines for the management of SRI treatment caused by acute bronchitis for emergency services, basic rooms and pediatric intensive care.

La insuficiencia respiratoria aguda (IRA) causada por bronquiolitis aguda (BA), cuya principal etiología es el virus respiratorio sincicial (VRS), es la principal causa de hospitalizaciones en menores de 2 años durante los meses de invierno, especialmente en grupos de riesgo. Su manejo se basa principalmente en medidas generales, administración de soporte respiratorio con oxigenoterapia estándar, ventilación no invasiva (VNI), ventilación mecánica invasiva (VMI) o la emergente terapia con cánula nasal de alto flujo (CNAF), que se ha transformado en los últimos años en una alternativa de fácil uso, bien tolerada, segura para ser usada en los servicios de urgencia, salas básicas y unidades de cuidados intensivos pediátricos (UCIP). La elección de la terapia a utilizar dependerá de la gravedad del paciente, del nivel de complejidad del centro asistencial y de la experiencia en las distintas modalidades de tratamiento del equipo de salud. Es fundamental realizar protocolos y guías de manejo de tratamiento de la IRA causada por BA tanto para servicios de urgencia, salas básicas como cuidados intensivos pediátricos.

Conditions of vulnerability to the inadequate treatment of bronchiolitis

SUMMARY OBJECTIVE To analyze clinical and demographic variables possibly associated with the prescriptions of non-recommended but routinely used therapies for infants with acute viral bronchiolitis. METHODS A cross-sectional study included hospitalized infants with bronchiolitis caused by the respiratory syncytial virus. Those with other associated infections and/or morbidities were excluded. The data were collected from medical records. RESULTS Among 120 cases, 90% used inhaled beta-agonists, 72.5% corticosteroids, 40% antibiotics, and 66.7% inhaled hypertonic saline solution. The use of bronchodilators did not present an independent association with another variable. More frequent use of corticosteroids was associated with low oximetry, longer hospitalization time, and age>3 months. Antibiotic therapy was associated with the presence of fever, longer hospitalization, and age>3 months. Inhaled hypertonic saline solution was associated with longer hospitalization time. CONCLUSIONS Non-recommended prescriptions were frequent. Corticosteroid and antibiotic therapy were associated with signs of severity, as expected, but interestingly, they were more frequently used in infants above 3m, which suggested less safety in the diagnosis of viral bronchiolitis in these patients. The use of bronchodilators was even more worrying since they were indiscriminately used, without association with another variable related to the severity or characteristics of the host. The use of the inhaled hypertonic solution, although not associated with severity, seems to have implied a longer hospitalization time. The identification of these conditions of greater vulnerability to the prescription of inappropriate therapies contributes to the implantation of protocols for the bronchiolitis treatment, for continuing education and for analysis of the effectiveness of the strategies employed.

RESUMO OBJETIVOS Analisar variáveis clínicas e demográficas possivelmente associadas às prescrições de terapêuticas não recomendadas, porém rotineiramente utilizadas, para lactentes com bronquiolite viral aguda. MÉTODOS Estudo transversal incluiu lactentes hospitalizados com bronquiolite por vírus sincicial respiratório. Excluídos aqueles com outras infecções e/ou morbidades. Dados coletados de prontuários. RESULTADOS Analisados 120 casos, para os quais foram prescritos: beta-agonistas inalatórios a 90%; corticosteroides a 72,5%, antibióticos a 40% e solução salina hipertônica inalatória a 66,7%. O uso de broncodilatadores não apresentou associação independente com outra variável. Maior uso de corticosteroide associou-se à baixa oximetria, maior tempo de internação e idade >3 meses. Antibioticoterapia associou-se à presença de febre, maior tempo de internação e idade >3 meses. Solução salina hipertônica inalatória associou-se a maior tempo de internação. CONCLUSÕES A frequência das prescrições não recomendadas foi elevada. Corticosteroide e antibioticoterapia foram associados a sinais de gravidade, como esperado, porém, interessantemente, foram mais utilizados nos lactentes com idade acima de 3 meses, o que sugeriu menor segurança no diagnóstico de bronquiolite viral nesses pacientes. O uso de broncodilatadores foi ainda mais preocupante, uma vez que foram indiscriminadamente utilizados, sem associação com outra variável, seja relacionada à gravidade, seja a características do hospedeiro. O uso de solução hipertônica inalatória, apesar de não associado à gravidade, parece ter implicado maior tempo de internação. A identificação dessas condições de maior vulnerabilidade à prescrição de terapêuticas inadequadas contribui para a implantação de protocolos para o tratamento da BVA, para educação continuada e para posteriores comparações e análises de eficácia das estratégias empregadas.

Temporal trend of hospitalizations for acute bronchiolitis in infants under one year of age in brazil between 2008 and 2015 / Tendência temporal das hospitalizações por bronquiolite aguda em lactentes menores de um ano no brasil entre 2008 e 2015

ABSTRACT Objective: To evaluate the trend of hospitalization for acute bronchiolitis in infants under one year of age, in the past eight years and after the implementation of the palivizumab immunization program in Brazil. Methods: The study is a retrospective analysis of data on infants younger than one year of age, who were hospitalized with acute bronchiolitis between 2008 and 2015 in Brazil. The Brazilian National Health System database was used. The rates of hospitalization in the pre-implementation (2008-2012) and post-implementation (2014-2015) periods of the palivizumab immunization program were evaluated. The total number of admissions in the same period was used as a comparison. Results: Between January 2008 and December 2015, 263,679 hospitalizations for bronchiolitis were recorded in infants younger than one year of age, 60% represented by boys. The incidence of hospitalization for bronchiolitis increased by 49% over this period (8.5 to 12.7 per 1,000 inhabitants per year). Between 2013 and 2014, the incidence rate of hospitalization for acute bronchiolitis decreased by 8% (12.5 to 11.5 per 1,000 inhabitants per year). However, in the second year of the program, hospitalization rate increased again by 10% (12.7 per 1,000 inhabitants per years). Conclusions: Acute bronchiolitis presented increasing rates of hospitalization over the study period. Hospitalization incidence for acute bronchiolitis declined one year after the implementation of palivizumab but increased again in the second year of the program.

RESUMO Objetivo: Avaliar a tendência de hospitalização por bronquiolite aguda (BA) em lactentes menores de um ano de idade nos últimos oito anos no Brasil e, secundariamente, após a implementação do programa de imunização por palivizumabe. Métodos: Análise retrospectiva dos dados de lactentes menores de um ano de idade, hospitalizados com diagnóstico de BA entre 2008 e 2015 no Brasil, utilizando o banco de dados do Sistema Único de Saúde (SUS). Foram avaliadas as taxas de hospitalização nos períodos pré-implementação (2008-2012) e pós-implementação (2014-2015) do programa de imunização por palivizumabe. O número total de internações no mesmo período foi utilizado como comparação. Resultados: Entre janeiro de 2008 e dezembro 2015 foram registradas 263.679 internações por bronquiolite em lactentes menores de um ano de idade, 60% representado por meninos. A incidência de hospitalização por bronquiolite aumentou em 49% ao longo desse período (8,5 para 12,7 por mil ­habitantes/­ano). Entre 2013 e 2014, a taxa de incidência de hospitalização por BA diminuiu 8% (12,5 para 11,5 por mil habitantes/ano). Porém, no segundo ano do programa, a taxa de internação aumentou novamente em 10% (12,7 por mil habitantes/ano). Conclusões: A BA apresentou taxas de hospitalização crescente ao longo do período estudado. A incidência de hospitalizações de BA apresentou declínio um ano após a implementação de palivizumabe e retornou à tendência crescente no segundo ano do programa.

Recurrent wheezing in preterm infants: Prevalence and risk factors / Sibilância recorrente em prematuros: prevalência e fatores de risco

ABSTRACT Objective: To evaluate the prevalence and risk factors associated with progression to recurrent wheezing in preterm infants. Methods: The cross-sectional study was carried out in 2014 and 2015 and analyzed preterm infants born between 2011 and 2012. The search for these children was performed in a university maternity hospital and a Special Immunobiological Reference Center. The evaluation was performed through a questionnaire applied during a telephone interview. Results: The study included 445 children aged 39 (18-54) months. In the univariate analysis, the risk factors with the greatest chance of recurrent wheezing were birth weight <1000 g, gestational age <28 weeks, living with two or more siblings, food allergy, and atopic dermatitis in the child, as well as food allergy and asthma in the parents. In the multivariate analysis, there was a significant association between recurrent wheezing and gestational age at birth <28 weeks, food allergy and atopic dermatitis in the child, and living with two or more children. Of the 445 analyzed subjects, 194 received passive immunization against the respiratory syncytial virus, and 251 preterm infants were not immunized. There was a difference between the gestational age of these subgroups (p < 0.001). The overall prevalence of recurrent wheezing was 27.4% (95% CI: 23.42-31.70), whereas in the children who received passive immunization it was 36.1% (95% CI: 29.55-43.03). Conclusions: Personal history of atopy, lower gestational age, and living with two or more children had a significant association with recurrent wheezing. Children with lower gestational age who received passive immunization against the respiratory syncytial virus had a higher prevalence of recurrent wheezing than the group with higher gestational age.

RESUMO Objetivo: Avaliar a prevalência e os fatores de risco associados à evolução para sibilância recorrente em prematuros. Métodos: O estudo transversal foi feito em 2014 e 2015 e analisou crianças prematuras nascidas entre 2011 e 2012. A busca dessas crianças foi feita em maternidade de hospital universitário e em um Centro de Referência para Imunobiológicos Especiais. A avaliação foi feita por questionário dirigido em entrevista telefônica. Resultados: O estudo incluiu 445 crianças com 39 (18-54) meses de vida. Na análise univariada, os fatores de risco com maior chance de sibilância recorrente foram peso de nascimento menor do que 1.000 g, idade gestacional menor do que 28 semanas, convivência com dois ou mais irmãos, alergia alimentar e dermatite atópica na criança e alergia alimentar e asma nos pais. Na análise multivariada houve associação significativa entre sibilância recorrente e idade gestacional ao nascer menor do que 28 semanas, alergia alimentar e dermatite atópica na criança e a convivência com duas ou mais crianças. Dos 445 sujeitos analisados, 194 receberam imunização passiva contra vírus sincicial respiratório e 251 eram prematuros não imunizados. Houve diferença entre a idade gestacional desses subgrupos (p < 0,001). A prevalência geral de sibilância recorrente foi 27,4% (IC 95%: 23,42-31,70) e nas crianças que receberam a imunização passiva foi 36,1% (IC 95%: 29,55-43,03). Conclusões: História pessoal de atopia, menor idade gestacional e convivência com duas ou mais crianças apresentaram associação significativa com sibilância recorrente. As crianças com menor idade gestacional, que receberam a imunização passiva contra o vírus sincicial respiratório, apresentaram maior prevalência de sibilância recorrente que o grupo de maior idade gestacional.

Virus isolation and genotype identification of human respiratory syncytial virus in Guizhou Province, China

ABSTRACT To investigate the genetic variation and molecular epidemiology characteristics of Human Respiratory Syncytial Virus (HRSV) in Guizhou Province, nasopharyngeal aspirates were collected from patients with acute respiratory infection (ARI) in Guizhou Provincial People's Hospital, from December 2017 to March 2018, and inoculated to Hep-2 cells to isolate HRSV. Cells that showed cytopathic effect (CPE) were then confirmed by indirect immunofluorescence assay and reverse transcription. The sequence of the PCR products was determined for HRSV isolates, and the genetic variation was analyzed. Out of 196 nasopharyngeal aspirate samples, HRSV were isolated in 39. The second hypervariable region at the 3' terminal of glycoprotein gene (HVR2) sequence analysis showed that subgroup A was dominant. Seventy-nine percent of the isolates belonged to subgroup A, ON1 genotype, and 21 % belonged to subgroup B, BA9 genotype, which indicates that the dominant HRSV circulating in Guizhou Province was subgroup A, genotype ON1, co-circulating with a less prevalent subgroup B, genotype BA9.

Rol del virus sincicial respiratorio en una cohorte de adultos mayores / Respiratory Syncytial Virus in the elderly adults

El rol de los virus respiratorios distintos de influenza en las infecciones respiratorias agudas en los adultos mayores ha sido probablemente subestimado. En los últimos años, los avances en técnicas moleculares de diagnóstico han hecho posible la identificación rápida del virus sincicial respiratorio humano (HRSV). Realizamos un estudio prospectivo observacional para evaluar el rol del HRSV en mayores de 65 años que se hospitalizaron por infecciones respiratorias en nuestra institución, ubicada en la ciudad de La Plata, provincia de Buenos Aires. Fueron reclutados 124 pacientes y el HRSV se detectó en 13, influenza B en 9 e influenza A en 8. La presentación clínica más frecuente de los The role of respiratory viruses other than influenza in acute respiratory tract infections among elderly adults has probably been underestimated. Recent advances in molecular diagnosis have made the rapid identification of human respiratory syncitial virus HRSV infection possible. We conducted a prospective observational study to evaluate the role of HRSV in elderly patients (>65 years of age) hospitalized for acute respiratory infections. A total of 124 patients were recruited, HRSV infection was identified in 13 patients, Influenza B in 9 patients and influenza A in 8 patients. The most frequent clinical presentation was bronchospasm and the infection was prevalent in patients with comorbidities. HRSV infections accounted for an important number of hospital admissions and has been associated with high mortality rates (23%). pacientes con HRSV fue el broncoespasmo y afectó principalmente a personas con comorbilidades. HRSV fue responsable de un número importante de internaciones por enfermedad respiratoria aguda en mayores de 65 años en nuestra institución y se asoció a mortalidad elevada (23%).

The role of respiratory viruses other than influenza in acute respiratory tract infections among elderly adults has probably been underestimated. Recent advances in molecular diagnosis have made the rapid identification of human respiratory syncitial virus HRSV infection possible. We conducted a prospective observational study to evaluate the role of HRSV in elderly patients (>65 years of age) hospitalized for acute respiratory infections. A total of 124 patients were recruited, HRSV infection was identified in 13 patients, Influenza B in 9 patients and influenza A in 8 patients. The most frequent clinical presentation was bronchospasm and the infection was prevalent in patients with comorbidities. HRSV infections accounted for an important number of hospital admissions and has been associated with high mortality rates (23%).

Etiología viral de las infecciones respiratorias agudas graves en una unidad de cuidados intensivos pediátricos / Viral etiology of severe acute respiratory infections in a pediatric intensive care unit

RESUMEN Objetivos. Identificar los principales agentes etiológicos virales en pacientes con infección respiratoria aguda grave (IRAG) hospitalizados en una Unidad de Cuidados Intensivos Pediátricos (UCIP) y analizar sus características clínicas. Materiales y métodos. Estudio longitudinal prospectivo en menores de cinco años hospitalizados por IRAG en la UCIP del Instituto Nacional de Salud del Niño en Lima, Perú. Se realizaron pruebas de inmunofluorescencia directa y RT-PCR en tiempo real para el diagnóstico de virus respiratorios en muestras de aspirado traqueal o hisopado nasofaríngeo. Resultados. Se incluyeron 117 pacientes. La mediana de edad fue cuatro meses, el 66% presentaron comorbilidad y el 91% requirieron ventilación mecánica. Se identificó monoinfección por virus respiratorios en el 47% y coinfección viral en el 2,6%, siendo el virus sincicial respiratorio subtipo A (VSR-A) el más frecuente. La mediana del tiempo de hospitalización fue de 21 días y 20 (17%) pacientes fallecieron. Se encontró asociación entre el antecedente de enfermedad pulmonar crónica y la infección por el VSR-A (p=0,045) y entre el síndrome de Down y la infección por virus influenza A (p=0,01). Después de controlar por potenciales factores de confusión, se halló que la cardiopatía congénita (RR: 3,1; IC 95%: 1,3-5,8; p=0,002) y la infección nosocomial (RR: 2,6; IC 95%: 1,0-5,3; p=0,01) incrementaron el riesgo de muerte en pacientes con IRAG. Conclusiones. El VSR-A fue la etiología viral más frecuente en menores de cinco años hospitalizados por IRAG en la UCIP. No se encontró asociación entre la infección viral y la sobrevida del paciente.

ABSTRACT Objectives. To identify the main viral etiological agents in patients with severe acute respiratory infection (SARI) hospitalized in a Pediatric Intensive Care Unit (PICU) and to analyze their clinical characteristics. Materials and Methods. Prospective longitudinal study in children under five years of age hospitalized due to SARI at the PICU of t Instituto Nacional de Salud del Niño (National Children´s Hospital) in Lima, Peru. Real-time direct immunofluorescence and RT-PCR tests were performed for the diagnosis of respiratory viruses on tracheal aspirate or nasopharyngeal swab samples. Results. We included 117 patients. Median age was four months, 66% had comorbidity and 91% required mechanical ventilation. Respiratory virus monoinfection was identified in 47% and viral co-infection in 2.6%, with the respiratory syncytial virus subtype A (RSV-A) being the most frequent. The median length of hospitalization was 21 days and 20 (17%) patients died. An association was found between a history of chronic lung disease and RSV-A infection (p=0.045), and between Down syndrome and influenza A virus infection (p=0.01). After controlling for potential confounders, congenital heart disease (RR 3.1; 95% CI: 1.3-5.8, p=0.002) and nosocomial infection (RR 2.6; 95% CI: 1.0-5.3, p=0.01) were found to increase the risk of death in patients with SARI. Conclusions. RSV-A was the most common viral etiology in children under five hospitalized by SARI at the PICU. No association was found between viral infection and patient survival.