Comparison of human metapneumovirus and respiratory syncytial virus in children admitted to a paediatric intensive care unit

Aim: To describe the clinical presentation and course of children admitted to the paediatric intensive care unit (PICU) with human metapneumovirus (hMPV) infection, and compare them with children admitted to the PICU with respiratory syncytial virus (RSV) infection. Methods: hMPV was identified by immunofluorescence in 22 children admitted to the PICU over a 16-month period. The medical records of these children were reviewed retrospectively, and their clinical and laboratory data were compared with 66 children admitted to the PICU with positive tests for RSV over the same period. Results: Children admitted to the PICU with hMPV were significantly older than children with RSV (P = 0.003). Children with hMPV presented more commonly with pneumonia or pneumonitis (29% vs. 16%), and less commonly with bronchiolitis (43% vs. 68%) than RSV (P = 0.13). Invasive ventilation was required in 10 patients (48%) with hMPV, and non-invasive ventilation was required in a further 5 (28%), similar to patients with RSV. Children with hMPV were more likely to have an underlying co-morbidity (P = 0.11). Conclusions: Children admitted to the PICU with hMPV have a similar disease presentation and severity as children admitted with RSV, including some with extremely severe disease who require additional ventilatory or cardiovascular support. Children with hMPV are likely to be older than those with RSV, and more likely to present with pneumonia and less likely to present with bronchiolitis.