Hospitalisations for respiratory syncytial virus bronchiolitis in Akershus, Norway, 1993–2000: a population-based retrospective study

Abstract

BackgroundRSV is recognized as the most important cause of serious lower respiratory tract illness in infants and young children worldwide leading to hospitalisation in a great number of cases, especially in certain high-risk groups. The aims of the present study were to identify risk groups, outcome and incidences of hospitalisation for RSV bronchiolitis in Norwegian children under two years of age and to compare the results with other studies.MethodsWe performed a population-based retrospective survey for the period 1993–2000 in children under two years of age hospitalised for RSV bronchiolitis.Results822 admissions from 764 patients were identified, 93% had one hospitalisation, while 7% had two or more hospitalisations. Mean annual hospitalisation incidences were 21.7 per 1.000 children under one year of age, 6.8 per 1.000 children at 1–2 years of age and 14.1 per 1.000 children under two years of age. 77 children (85 admissions) belonged to one or more high-risk groups such as preterm birth, trisomy 21 and congenital heart disease. For preterm children under one year of age, at 1–2 years of age and under two years of age hospitalisation incidences per 1.000 children were 23.5, 8.7 and 16.2 respectively. The incidence for children under two years of age with trisomy 21 was 153.8 per 1.000 children.ConclusionWhile the overall hospitalisation incidences and outcome of RSV bronchiolitis were in agreement with other studies, hospitalisation incidences for preterm children were lower than in many other studies. Age on admission for preterm children, when corrected for prematurity, was comparable to low-risk children. Length of hospitalisation and morbidity was high in both preterm children, children with a congenital heart disease and in children with trisomy 21, the last group being at particular high risk for severe disease.

Risk factors for respiratory syncytial virus hospitalisation in children with heart disease

“…The high risk of RSV hospitalisation in children with Down syndrome is in accordance with other studies showing both increased susceptibility and severity of respiratory tract infections in these children 12 13 14 15. This may, among other factors, be related to abnormal development of the lungs leading to decreased airway branching, which is known to occur in children with Down syndrome 16.…”

Clinical and Epidemiologic Features of Respiratory Syncytial Virus

“…In comparison to the hospitalization rates for influenza or parainfluenza viruses in this same population, rates for RSV were 3 times higher among children under 5 years of age and 6-8 times greater among infants. Similar rates of RSV-associated hospitalizations have been reported from other industrialized countries with rates reported of 9-28/1,000 children for the first year of life and 3-6/1,000 for children\5 years of age (Fjaerli et al 2004;Forster et al 2004;Nicholson et al 2006;van Gageldonk-Lafeber et al 2005;Eriksson et al 2002).…”

Acute bronchiolitis in infancy as risk factor for wheezing and reduced pulmonary function by seven years in Akershus County, Norway

“…Acute RSV bronchiolitis is a major health problem in our region with a mean hospitalisation incidence for the period 1993–2000 in infants of 23.6 per 1.000 [35]. Many infants with acute viral bronchiolitis, not only those due to RSV, will have episodes of recurrent wheezing, resubmissions to hospital and reduced lung function, at least up to age seven years.…”