Human metapneumovirus in central China, 2024–2025: epidemiology, co-infections, and temporal dynamics

Human metapneumovirus (HMPV) is a major cause of acute respiratory infections in children, but comprehensive data from sentinel surveillance in the post‑pandemic period remain limited. Understanding its epidemiology and co‑infection patterns is critical for surveillance and prevention. We analyzed 36,143 respiratory specimens from ILI/SARI patients in Henan, China (2024–2025) using multiplex PCR for HMPV and 14 other pathogens. Positivity rates, enrichment ratios, co‑infection patterns, pathogen associations (OR/PR), and temporal dynamics (cross‑correlation and regression) were assessed. Overall HMPV positivity was 3.96% (1,432/36,143), with a sharp inter-year difference: 7.1% in 2024 vs. 1.7% in 2025, peaking at 26.2% during week 48. Children aged 3–5 years had the highest positivity (8.6%; enrichment ratio 2.18). Co-infections occurred in 56.2% of HMPV-positive cases, predominantly with Streptococcus pneumoniae and Haemophilus influenzae. HMPV showed positive associations with these bacteria (OR = 2.01 and 1.47, respectively) but negative associations with influenza virus (OR = 0.20) and respiratory syncytial virus (RSV) (OR = 0.17). HBoV also showed a positive association (OR = 1.66). RSV positivity at a 1-week lag had a positive effect on HMPV (β = 0.15, P = 0.048). HMPV was frequently detected in pediatric ILI/SARI patients during 2024–2025, with high rates of bacterial co‑detection. The temporal lead‑lag relationship with RSV underscores the need for integrated surveillance and age‑targeted prevention. The marked 2024 resurgence warrants continued monitoring to determine whether the observed patterns represent a short‑term anomaly or a sustained change in HMPV circulation.