Abstract Background Adenovirus (AdV), influenza A virus (FluA), influenza B virus (FluB), respiratory syncytial virus (RSV), rhinovirus (RV), and Mycoplasma pneumoniae (MP) are the primary pathogens causing acute respiratory infections in children. However, comprehensive and multifactorial analyses of their epidemiological features, such as seasonality and age specificity, remain limited. Methods We performed a retrospective analysis of 68,982 children (aged 0–18 years) with acute respiratory infections who underwent multiplex PCR testing at Chengdu Women and Children’s Central Hospital between March 1, 2023, and February 28, 2025. Single-pathogen positivity rates were compared using Pearson’s chi-square test. Multivariate logistic regression was used to evaluate the associations between age group, season, sex, and care setting and pathogen detection, reporting adjusted odds ratios (ORs) and 95% confidence intervals (CIs) with adolescence, autumn, female sex, and inpatient status as reference categories. Co-infection patterns were analyzed by constructing a network based on pairwise co-detection frequencies, calculating node degrees and edge weights to identify predominant mixed-infection combinations. Results Overall PCR positivity was 53.1% (36,677/68,982). The positivity rate increased from 38.8% in infants to 63.5% in school-aged children (χ² = 2276.7; P < 0.001). Among all pathogens, RV remained common across all age groups, with an overall positivity rate of 18.1%. Compared to adolescents, infants had significantly higher odds of RSV detection (OR = 7.82; 95% CI 5.53–11.04); school-aged children had higher odds of MP detection (OR = 2.82; 95% CI 2.39–3.32). Males exhibited slightly higher overall positivity than females (53.6% vs. 52.6%; χ² = 7.41; P = 0.007). Positivity was higher in winter and autumn than in summer (58.1% vs. 46.6%; χ² = 628.6; P < 0.001). Outpatients had higher positivity rates than inpatients (63.2% vs. 51.1%; χ² = 586.7; P < 0.001). Seasonal analysis showed that AdV peaked in summer (OR = 1.46; 95% CI 1.38–1.55); RV peaked in autumn and spring (summer OR = 0.62; 95% CI 0.59–0.65); MP peaked in autumn; and RSV and influenza B virus peaked in winter (RSV OR = 2.82; 95% CI 2.63–3.03; FluB OR = 4.70; 95% CI 3.94–5.60). Co-infection analysis revealed that the most common co-infection pattern was RV + MP, with 1,009 cases identified in hospitalized patients. Conclusions Age, season, and care setting significantly affect pediatric respiratory pathogen detection. These findings may inform targeted public health surveillance and respiratory infection prevention strategies.
Chen et al. (Wed,) studied this question.