Epidemiology of respiratory syncytial virus bronchiolitis in hospitalized infants in Greece

Abstract

New therapies have been introduced for the prophylaxis and treatment of respiratory syncytial virus (RSV) infection in recent years. The aim of the study was to determine the epidemiological and clinical characteristics of infants hospitalized with bronchiolitis in our area. All patients under 1 year of age admitted with acute bronchiolitis during four consecutive RSV seasons from February 1, 1997 to June 30, 2000 were enrolled in the study. The records of patients admitted during the first season were reviewed retrospectively while the rest were followed prospectively. A total of 636 infants with bronchiolitis were admitted and RSV infection was documented in 61% of those tested. Admission to intensive care unit (ICU) was required for 6.2% of them and was more common in premature infants (26%) (p < 0.001). Case fatality rate was 0.7% (overall 0.3%). RSV bronchiolitis accounted for about 12% of all infant admissions during the 5 months of the yearly outbreak. Patients with documented RSV infection had a more severe illness with a higher ICU admission rate (6 vs. 1%, p = 0.008) and longer duration of hospitalization (mean 6.3 vs. 5.3 days, p < 0.001) compared to those who tested negative. Although none of the patients had a positive blood culture on admission a considerable number of them (210/636, 33%) were treated with antibiotics. RSV infection has a significant impact on infant morbidity in our settings which is more serious among those born prematurely. Documentation of RSV infection may be a marker of more severe illness in infants hospitalized with bronchiolitis. Antibiotic use has to be restricted since the occurrence of a serious bacteraemic illness on admission is a very rare event.

Defining the Risk and Associated Morbidity and Mortality of Severe Respiratory Syncytial Virus Infection Among Preterm Infants Without Chronic Lung Disease or Congenital Heart Disease

“…Results from a number of studies show that preterm infants are at an increased risk for morbidity and increased rates of health care resource utilization, including longer duration of illness and longer hospital stays, compared with full-term infants [5, 8, 14, 16, 29, 46, 50, 57, 64–72]. Data also show that nosocomial RSV infection in high-risk infants, including preterm infants, often follows a severe course of disease [73].…”

Medical and Economic Impact of a Respiratory Syncytial Virus Outbreak in a Neonatal Intensive Care Unit

“…The mean number of days on the ventilator was 12.2 days (range, [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. The most severely affected infant (infant C) required extracorporeal membrane oxygenation (ECMO) for 9 days.…”

Association of Weather Conditions with Childhood Admissions for Wheezy Bronchitis or Asthma in Athens

“…Several other outdoor or indoor environmental triggers or events could also cause these patterns. An increase in various air pollutants has been related to meteorological conditions [15, 16], seasonality of viral infections has been repeatedly documented [17, 18], and school and summer holidays are consistently disrupting each calendar year [19]. …”

“…The seasonal distribution of admitted children with viral respiratory infections in Athens is very similar to that of asthma, especially for the 0- to 4-year age group [18, 36]. Moreover, the recent finding that high exposure to NO 2 in the week before the start of a respiratory viral infection is associated with an increase in the severity of a resulting asthma exacerbation shows the intercorrelation of the various implicated triggering factors [37].…”