Bronchiolitis Caused by Respiratory Syncytial Virus in an Area of Portugal: Epidemiology, Clinical Features, and Risk Factors

  • P. FloresEmail author
  • H. Rebelo-de-Andrade
  • P. Gonçalves
  • R. Guiomar
  • C. Carvalho
  • E. N. Sousa
  • F. T. Noronha
  • J. M. Palminha


The aim of the present study was to analyse the clinical and epidemiological characteristics of bronchiolitis caused by respiratory syncytial virus (RSV) in 225 children observed in a paediatric hospital in Lisbon, Portugal, and to determine the clinical, epidemiological, or laboratory parameters that correlate with greater severity of the disease. This prospective study included hospitalised and ambulatory children younger than 36 months of age with a diagnosis of bronchiolitis and was conducted during two consecutive RSV epidemiological seasons (November–March 2000/01 and 2001/02). The median age of the patients was 5 months, and the male-to-female ratio was 1.6:1. RSV was isolated in 60.9% of patients, predominantly in the hospitalised group. The subtype A:B ratio was 7.4:1 and was similar in both seasons. RSV-positive patients were younger, had more severe clinical forms of bronchiolitis, and fewer changes in leucocyte total and differential counts. Among infected patients, higher clinical severity scores occurred in association with first wheezing episodes, overcrowded households, attendance at day-care centres, or prematurity (<36 weeks). This first prospective study of RSV epidemiology in Portugal provides a foundation for appropriate surveillance programmes of RSV infection in this country. A multicentre study is desirable in order to delineate optimal prophylactic and therapeutic guidelines for RSV infection in Portugal.


Respiratory Syncytial Virus Bronchiolitis Respiratory Syncytial Virus Infection Palivizumab Acute Bronchiolitis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This study was supported by a grant from the “Comissão de Fomento para a Saúde” of the Portuguese Ministry of Health. The authors would like to thank Carlos Aguiar, M.D., for the revision of the manuscript. The experiments described herein comply with the current laws of Portugal.


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Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • P. Flores
    • 1
    Email author
  • H. Rebelo-de-Andrade
    • 2
  • P. Gonçalves
    • 2
  • R. Guiomar
    • 2
  • C. Carvalho
    • 1
  • E. N. Sousa
    • 1
  • F. T. Noronha
    • 1
  • J. M. Palminha
    • 1
  1. 1.Servico de PediatriaHospital de S. Francisco XavierLisbonPortugal
  2. 2.Unidade de Vírus Respiratórios e EntéricosInstituto Nacional de SaúdeLisbonPortugal

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