Objective To determine if a validated, risk-scoring tool (RST), developed by the Canadian PICNIC group to target moderate and high-risk, 33–35-week gestational age infants for immunisation during the respiratory syncytial virus (RSV) season would also predict RSV hospitalisation and emergency room visits in term infants with RSV infection.
Methods 72 RSV-positive cases were identified retrospectively, during the 2006–2007 RSV season. A questionnaire/chart review was conducted on 68/72 cases (four declined consent), to determine risk categories based on the RST. Four trained abstractors extracted pertinent data from the medical records of RSV-positive patients. Mean, SD, and percentages were used to describe study variables for hospitalised and emergency room patients. Chi-square was used for the analysis of categorical data and analysis of variance for comparisons within and between groups.
Results The majority of infants scored in the low-risk category (n = 44), versus moderate (n = 16) or high risk (n = 8). The mean RST scores for those admitted to the paediatric intensive care unit/ward, the ward only, or those discharged home from the emergency room were 48.3, 40.9, and 35.5, respectively. The mean number of risk factors for those discharged home versus those admitted was 2.5 (SD 1.3) and 2.97 (SD 1.13), respectively (p = 0.15). Only two out of eight cases in the high-risk group required intensive care.
Conclusions Overall, the RST did not discriminate the risk of emergency room visits or RSV hospitalisation in term infants. A larger study is necessary to establish risk factors that more accurately determine RSV hospitalisation among term infants in order to target palivizumab prophylaxis cost-effectively.