Serological Survey of Hantavirus in Inhabitants from Tropical and Subtropical Areas of Brazil

Brazil has reported more than 1,600 cases of hantavirus cardiopulmonary syndrome (HPS) since 1993, with a 39% rate of reported fatalities. Using a recombinant nucleocapsid protein of Araraquara virus, we performed ELISA to detect IgG antibodies against hantavirus in human sera. The aim of this study was to analyze hantavirus antibody levels in inhabitants from a tropical area (Amazon region) in Rondonia state and a subtropical (Atlantic Rain Forest) region in Sao Paulo state, Brazil. A total of 1,310 serum samples were obtained between 2003 and 2008 and tested by IgG-ELISA, and 82 samples (6.2%), of which 62 were from the tropical area (5.8%) and 20 from the subtropical area (8.3%), tested positive. Higher levels of hantavirus antibody were observed in inhabitants of the populous subtropical areas compared with those from the tropical areas in Brazil

Detection of influenza, parainfluenza, adenovirus and respiratory syncytial virus during asthma attacks in children older than 2 years old

Background: Viral upper respiratory tract infections (URTI) have been correlated with the onset of asthma attacks in children and viral identification was reported in 14-49 por ciento of nasal samples. The aim of the present study was to detect influenza, parainfluenza, adenovirus and respiratory syncytial virus (RSV) in older children during acute asthma attacks.Methods: A total of 104 children (2-14 years) were included in four groups: group I: asthmatics with acute attack and URTI; group II: asthmatics without URTI (group I children, 30 days later); group III: non-asthmatics with URTI; group IV: non-asthmatic, asymptomatic children. A diagnosis of URTI was considered when (3 symptoms (cough and/or sneeze, nasal obstruction, hypertrophy of turbinates, pain and/or retropharynx hyperemia, headache and fever) in asthmatics and at least 2 symptoms in non-asthmatics were present, starting within 7 days.Samples of nasal mucosa cells (n = 123) were collected, and culture and indirect immunofluorescence were carried out to identify respiratory syncytial virus, adenovirus, influenza A and B, parainfluenza 1,2 and 3 and rhinovirus.Results: Viral identification rates were higher in the asthmatic groups: 13.9 por ciento in group I, 11.1 por ciento in group II; 2.8 por ciento in group III and 0 in group IV. The following viruses were identified: RSV 2/36, rhinovirus 1/36, adenovirus 1/36 and parainfluenzae 1/36 in group I; adenovirus 2/18 in group II; RSV 1/36 in group III.Conclusions: The rate of viral identification was higher in asthmatic children, whether symptomatic or not, suggesting a possible susceptibility to viral infections. Virus could also be a triggering factor in attacks, although it is not the most preponderant in older children (AU)

Antecedentes: Las infecciones virales del tracto respiratorio superior (IVTRS) se han relacionado con la aparición de ataques de asma en niños, habiéndose identificado virus en un 14-49 % de muestras nasales. El objetivo del presente estudio fue detectar el virus de la gripe, parainfluenza, adenovirus y virus respiratorio sincitial (VRS) en niños mayores de 2 años durante ataques agudos de asma. Métodos: Se distribuyeron 104 niños (de 2 a 14 años) en 4 grupos: GI: asmáticos con ataque agudo e IVTRS; GII: asmáticos sin IVTRS (niños del grupo GI, 30 días después); GIII: no asmáticos con IVTRS; GIV: niños no asmáticos y asintomáticos. El diagnóstico de IVTRS se estableció en presencia de ≥ 3 síntomas (tos y/o estornudos, obstrucción nasal, hipertrofia de los cornetes, dolor y/o hiperemia en la retrofaringe, dolor de cabeza y fiebre) en los asmáticos y como mínimo de 2 síntomas en los no asmáticos, dentro de los primeros 7 días. Se extrajeron muestras de células de la mucosa nasal (n = 123), que se sometieron a cultivo e inmunofluorescencia indirecta para identificar el virus respiratorio sincitial, adenovirus, gripe A y B, parainfluenza 1, 2 y 3 y rinovirus. Resultados: Los índices de identificación viral fueron superiores en los grupos de asmáticos: 13,9% en el grupo GI; 11,1 % en el GII; 2,8 % en el GIII y 0 en el GIV. Se identificaron los siguientes virus: VRS 2/36, rinovirus 1/36, adenovirus 1/36 y parainfluenza 1/36 en el grupo GI; adenovirus 2/18 en el GII; VRS 1/36 en el GIII. Conclusiones: El índice de identificación viral fue superior en los niños asmáticos, ya fueran sintomáticos o no, lo que sugiere una posible susceptibilidad a las infecciones víricas. Asimismo, los virus podrían asociarse a los ataques como factor desencadenante, si bien no son el factor más preponderante en niños mayores de 2 años (AU)