Abstract / Summary
Abstract Human metapneumovirus (HMPV) is a leading cause of paediatric acute respiratory infections, yet its post-pandemic epidemiology and environmental drivers remain unclear. In a retrospective multi-centre surveillance of 108,701 hospitalized children across Fujian, China (June 2019 – December 2025), HMPV was detected in 6.06% (6,589/108,701). Following near-elimination during pandemic restrictions, an atypical spring surge emerged in 2025, peaking at 36.84% positivity in March. Children aged 3–6 years had the highest rate (8.43% overall; 15.35% at surge), and post-pandemic positivity was higher in females (P < 0.001). Co-infection (25.71%) was dominated by rhinovirus. Positivity correlated positively with Air Quality Index and PM2.5, and negatively with temperature measures. LASSO regression identified minimum temperature (negative) and AQI (positive) as the most stable predictors. Lower temperatures and poorer air quality are thus major drivers of HMPV circulation, with a seasonal shift from winter to spring – calling for environment-tailored prevention strategies in paediatric populations.