Influenza virus surveillance among young children in São Paulo, Brazil: the impact of vaccination.

This study assessed the presence of influenza virus among young children and the coverage of vaccination from 2010 to 2012 in São Paulo, Brazil. Our results demonstrated a lower rate of influenza detection and a predominance of influenza B. A decrease of coverage vaccination through the surveillance periods was observed.

Surveillance of influenza A H1N1 2009 among school children during 2009 and 2010 in São Paulo, Brazil.

INTRODUCTION: Influenza A H1N1 2009 is associated with a high morbidity rate among children around the world, including Brazil. This survey was conducted on samples of symptomatic children (< 12 years) to investigate the influenza virus as the etiological agent of respiratory infections in a day care school in a health facility during the first and second pandemic wave of H1N1 (2009-2010) in São Paulo, Brazil. METHODS: Influenza infections were determined by real-time PCR in 34% (47/137) of children with a median age of 5 years (8 months - 12 years), from June to October 2009 and in 16% (14/85) of those with median age of 6 years (1-12 years), from March to November 2010. RESULTS: In general, most positive cases (64%) occurred in children aged 5-12 years, this age group was significantly the most affected (39.8%, p = 0.001, OR = 8.3, CI 95% 1.9-36.9). Wheezing was reported by 31% (19/61) and dyspnea by 23% (14/61) of the studied patients. An outbreak of influenza H1N1 with an attack rate of 35.7% among children (median age 6 years) was documented in April 2010, before the vaccination campaign against the pandemic virus was extended for children up to 5 years in Brazil. CONCLUSIONS: Therefore, the study reinforces the recommendation to immunize school children to reduce the incidence of the disease.

Influenza virus surveillance among young children in São Paulo, Brazil: the impact of vaccination

This study assessed the presence of influenza virus among young children and the coverage of vaccination from 2010 to 2012 in São Paulo, Brazil. Our results demonstrated a lower rate of influenza detection and a predominance of influenza B. A decrease of coverage vaccination through the surveillance periods was observed.

Surveillance of influenza A H1N1 2009 among school children during 2009 and 2010 in São Paulo, Brazil / Vigilância de influenza A H1N1 2009 entre crianças em idade escolar durante os anos de 2009 e 2010 em São Paulo, Brasil

INTRODUCTION: Influenza A H1N1 2009 is associated with a high morbidity rate among children around the world, including Brazil. This survey was conducted on samples of symptomatic children (< 12 years) to investigate the influenza virus as the etiological agent of respiratory infections in a day care school in a health facility during the first and second pandemic wave of H1N1 (2009-2010) in São Paulo, Brazil. METHODS: Influenza infections were determined by real-time PCR in 34% (47/137) of children with a median age of 5 years (8 months - 12 years), from June to October 2009 and in 16% (14/85) of those with median age of 6 years (1-12 years), from March to November 2010. RESULTS: In general, most positive cases (64%) occurred in children aged 5-12 years, this age group was significantly the most affected (39.8%, p = 0.001, OR = 8.3, CI 95% 1.9-36.9). Wheezing was reported by 31% (19/61) and dyspnea by 23% (14/61) of the studied patients. An outbreak of influenza H1N1 with an attack rate of 35.7% among children (median age 6 years) was documented in April 2010, before the vaccination campaign against the pandemic virus was extended for children up to 5 years in Brazil. CONCLUSIONS: Therefore, the study reinforces the recommendation to immunize school children to reduce the incidence of the disease.

INTRODUÇÃO: Influenza A H1N1 2009 está associado com uma alta taxa de morbidade entre crianças ao redor do mundo, incluindo o Brasil. Esta pesquisa foi realizada em amostras de crianças sintomáticas (< 12 anos) em uma creche escola para filhos de funcionários do hospital durante a primeira e segunda onda pandêmica (2009-2010) em São Paulo, Brasil. MÉTODOS: Infecções pelo vírus influenza foram determinadas por PCR em tempo real em 34% (47/137) em crianças com idade mediana de 5 anos (8 meses -12 anos), entre junho e outubro de 2009 e em 16% (14/85) daquelas com mediana de idade de 6 anos (1-12 anos), de março a novembro de 2010. RESULTADOS: Em geral, a maioria dos casos positivos (64%) ocorreu em crianças com idade entre 5-12 anos, esta faixa etária foi significativamente a mais afetada (39,8%, p = 0,001, OR = 8,3, CI 95%: 1,9-36,9). Chiado foi relatado em 31% (19/61) e dispnéia em 23% (14/61) dos pacientes estudados. Um surto de gripe H1N1 com uma taxa de ataque de 35,7% entre as crianças (mediana de idade de 6 anos) foi documentado em abril de 2010, antes da extensão da campanha de vacinação contra o vírus pandêmico para crianças até 5 anos no Brasil. CONCLUSÕES: Portanto, neste estudo reforça a recomendação para imunizar crianças em idade escolar para reduzir a incidência da doença.

Estudo comparativo de detecção de metapneumovírus humano pelos métodos de PCR e imunofluorescência direta / Comparative study of human metapneumovirus detection by PCR and direct immunofluorescence methods

INTRODUÇÃO: O metapneumovírus humano (MPVh) causa infecções respiratórias em crianças, adultos e idosos imunodeprimidos. O diagnóstico é realizado por imunofluorescência (IF) ou biologia molecular. OBJETIVO: Detectar o MPVh em amostras clínicas pelos métodos de reação em cadeia da polimerase (PCR) e imunofluorescência direta (IFD). RESULTADOS: Das 202 amostras, a positividade foi de 2 por cento e 4 por cento para IFD e RT-PCR, respectivamente. Sensibilidade e especificidade da IFD foram de 50 por cento e 100 por cento, respectivamente, considerando o PCR com transcrição reversa (RT-PCR) como padrão-ouro. CONCLUSÃO: O estudo indica a RT-PCR como o melhor método para a identificação de MPVh em amostras clínicas respiratórias e mostra a importância da padronização do teste para inclusão na rotina laboratorial.

INTRODUCTION: Human metapneumovirus (HMPV) is responsible for respiratory infections in children and immunocompromised adults and elders. It is commonly diagnosed by immunofluorescence or molecular biology. OBJECTIVE: To detect HMPV in clinical samples by polymerase chain reaction (PCR) and direct imunofluorescence (DIF) methods. RESULTS: Two percent of 202 samples were positive for DIF and 4 percent of them for reverse transcriptase PCR (RT-PCR), respectively. Considering RT-PCR as gold standard, DIF sensitivity and specificity were 50 percent and 100 percent, respectively. CONCLUSION: Not only does the study show that RT-PCR is the best method for HMPV detection in clinical respiratory samples but it also substantiates the importance of test standardization in laboratory routine.