Epidemiological trends and climate-driven dynamics of children respiratory infections in Lanzhou, China: a multi-pathogen time-series analysis.

OBJECTIVE

The COVID-19 pandemic significantly affected the transmission of respiratory pathogens worldwide. This study aimed to describe the epidemiological characteristics of respiratory infections among children in Lanzhou, China, during the post-pandemic period and to investigate how meteorological factors influence the transmission of respiratory pathogens in the Lanzhou region.

METHODS

During the study period, 42.5% of children tested positive for respiratory pathogens (32.8% single, 9.7% mixed infections). Predominant pathogens were influenza virus (IFV, 12.3%), adenovirus (HAdV, 8.2%), rhinovirus (RV, 7.5%), and respiratory syncytial virus (RSV, 6.7%). RSV and IFV peaked in infants <1 year (14.1% and 13.5%), while Mycoplasma pneumoniae (MP) was highest in school-aged children (8.5%). Mixed infections increased with age (2.8% to 11.6%), with no sex differences. Seasonal patterns varied: IFV peaked in winter (26.9%), enteroviruses in summer (18.9%), and RSV showed bimodal winter-spring distribution. IFV negatively correlated with temperature (r = -0.50) and positively with atmospheric pressure (r = 0.37). RSV negatively correlated with temperature (r = -0.49), while MP positively correlated with humidity and pressure.Nonlinear lag modeling showed immediate meteorological effects (0-week lag). IFV showed elevated risk under extreme low temperatures and high pressure (RR: 10.395 and 18.597), though wide confidence intervals warrant caution. HAdV and MP risks increased similarly. Conversely, HPIV and RV showed protective associations at low temperatures or high wind speeds. Wind speed appeared protective against most pathogens, but this observational finding requires interventional validation.

CONCLUSION

Pediatric respiratory pathogen prevalence in Lanzhou exhibited distinct age-dependent and seasonal characteristics, with pathogen-specific meteorological associations. Detection risks for IFV, RSV, HAdV, and MP increased with low temperatures and high pressure, while RV and HPIV showed opposite patterns. The protective wind speed effect suggests ventilation improvements may reduce transmission risk, though this hypothesis-generating conclusion requires further validation. These findings inform age-stratified, seasonally-adapted prevention strategies and meteorological early warning systems.