Acute Lower Respiratory Infections in childhood: Prevalence in the state of Rio de Janeiro, BRAZIL
Session I – Paranhos-Baccala – Abstract 1 of 2
Title of Contribution: Acute Lower Respiratory Infections in childhood: Prevalence in the state of Rio de Janeiro, BRAZIL
Author(s): Jean-Noel Telles1, Stéphane Pouzol1, Carlos H. Azeredo2, Patricia F.B.M. Costa 2, Joseane S. de O. Pereira2, , Magali Perret1, Florence Komurian-Pradel1, François Topin3, Guy Vernet1, Richard Janeczko3, Marilda Siqueira2, Gláucia Paranhos-Baccalà1
Affiliation(s):1Emerging Pathogens Laboratory, Fondation Mérieux, IFR128 BioSciences Lyon-Gerland, Lyon-France; 2 Virology Laboratory, IOC-FIOCRUZ, Rio de Janeiro-Brazil; 3 Luminex Corporation, Toronto-Canada
Abstract: Acute Lower Respiratory Infections (ALRI), i.e. viral or bacterial bronchiolitis and pneumonia, represent a major public health problem because of their worldwide occurrence, ease of spread in the community and considerable morbidity and mortality. A retrospective epidemiological study, during the two last consecutive winter seasons (2006/2008), was performed with 210 infants with bronchiolitis (n=159) and children with pneumonia (n=51) hospitalized in Paediatric Service at the General Hospital of Bonsucesso in the state of Rio de Janeiro, Brazil. Nucleic acids from nasal aspirates were obtained using EasyMag extractor (bioMérieux SA) and 20 respiratory viruses targets were detected using the Luminex xTAG Respiratory Panel (RVP) assay. Bocavirus, Chlamydia and Mycoplasma were identified using in-house quantitative real-time PCR or real-time NASBA. By using the Luminex xTAG Respiratory Panel (RVP) assay competed by our in-house techniques a great number of specimens were found positive for all the viruses and atypical bacteria tested (87.4% and 67% for bronchiolitis and pneumonia, respectively). The most common causative agent in the bronchiolitis cohort was Bocavirus, 25/159 (16%) specimens with viral loads ranging from 7.6e102 to 7e1010 copies/ml and not RSV, as expected. In this study RSV was only found in 9% of the cases. Enterovirus/Rhinovirus represented the second most common viral pathogen with 17/159 (11%). Other respiratory viruses were also found but to a lower extent. Multiple co-detections were identified in 50 of 159 of the bronchiolitis cases (31.4%) infants. Among these the most represented were Enterovirus/Rhinovirus plus Bocavirus (17/50) and RSVA/B plus Bocavirus (10/50). In the pneumonia cohort (n=51), the same profile was found with Bocavirus as the main pathogen detected (13.7%), followed by Enterovirus/Rhinovirus (11.8%). Concerning the multiple co-detection in pneumonia cohort (13/51) Bocavirus is involved in 69% of cases. Interestingly, in the two cohorts Influenza A virus was found in only one bronchiolitis children. This is the first complete molecular epidemiology study in the state of Rio de Janeiro, Brazil in children hospitalized with bronchiolitis and pneumonia using multiplex respiratory detection technologies. We were able to determine the etiology and epidemiology of most ALRIs and trace the seasonal profile of the commonest respiratory viruses among young children. This study confirms that Bocavirus is the main aetiology agent either in pneumonia or bronchiolitis.
