Human metapneumovirus infection in hospitalized children: a four-year retrospective study from a tertiary pediatric hospital

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Human metapneumovirus (hMPV) is an important viral cause of acute respiratory infections, particularly in young children, and may lead to hospitalization for lower respiratory tract disease. However, detailed clinical data from hospitalized pediatric cohorts remain limited. This study combined two complementary datasets from a tertiary pediatric hospital in Palermo, Italy. The hospital microbiology dataset included all PCR-confirmed hMPV detections recorded from October 2021 to May 2025 ( n = 636, including 560 pediatric cases) and was used only to describe temporal distribution. The clinical cohort comprised 78 of the pediatric cases who were hospitalized in the Pediatric Infectious Diseases Unit between January 2022 and May 2025 and had complete clinical records. Demographic, clinical, laboratory, radiological, and therapeutic data were collected and analyzed through IBM SPSS Statistics using descriptive statistics and exploratory bivariate analyses. Continuous variables were summarized as median and interquartile range (IQR), while categorical variables were reported as absolute frequencies and percentages. Comparisons between children who received antibiotics and those who did not were performed using Pearson’s chi-square or exact tests, as appropriate. Associations between categorical predictors and length of hospital stay were explored using the Mann–Whitney U test. Correlation with age was assessed using Spearman’s coefficient. The median age of hospitalized children was 14 months (IQR 3–30). The most frequent signs and symptoms were cough (64;82.1%), fever (59;75.6%), and signs of respiratory distress, including tachypnea (48;61.5%) and subcostal retraction (38;48.7%). Hyporexia (32;41%) and coryza (29;37.2%) were also common. Chest X-ray was performed in 41 (52.6%) patients and showed abnormal findings in all cases, most commonly consolidation patterns. Viral coinfections were detected in 25.6% of patients, and bacterial organisms were detected in 24.4%. Oxygen support was required in 60.3% of cases, and five patients (6.4%) required pediatric intensive care admission. Antibiotics were prescribed in 70.5% of patients, although bacterial organisms were detected in only 24.4%. Our findings describe the clinical characteristics and management of hospitalized children with hMPV infection in a tertiary pediatric center, highlighting the clinical relevance of hMPV among hospitalized children in our center. Moreover, the high rate of antibiotic prescription observed in this cohort highlights the diagnostic challenges in distinguishing viral from bacterial respiratory infections and underscores the importance of improved antimicrobial stewardship and virological surveillance in pediatric respiratory disease.