Abstract
This study aims to investigate the prevalence of pneumonia in preschool children in Haikou City and assess the correlates of indoor environmental factors on this condition. A cross-sectional survey was conducted from December 2020 to January 2021. Using a stratified random sampling method, eight kindergartens in Haikou City were selected for a questionnaire-based investigation. Logistic regression analysis was performed to assess the associated factors for Pneumonia in Preschool Children. The prevalence of pneumonia among the 3,049 preschool children was 20.44%. This study reveals that pneumonia in preschool children is influenced by both modifiable environmental exposures and non-modifiable host factors. Among the key modifiable associated factors within the household, paternal smoking(OR = 1.253, P = 0.030) and keeping furry pets(OR = 1.713, P = 0.017) significantly increased the risk, whereas the use of a fresh air filtration system(OR = 0.566, P = 0.018) showed a strong protective effect. These actionable findings suggest that targeted interventions, such as promoting air filtration and reducing indoor airborne pollutants from smoking and pets, could effectively lower disease prevalence. Additionally, non-modifiable factors like female sex (OR = 0.823, P = 0.036)and a family history of allergies (OR = 1.423, P < 0.001) help identify children who may benefit most from such environmental interventions. Pneumonia in preschool children is associated with various factors, including demographic characteristics, exposure to tobacco smoke, pet ownership, and the presence of air filtration systems in the home. This study found that avoiding these associated factors may reduce the prevalence of pneumonia.
Data availability
The datasets generated and/or analyzed during the current study are not publicly available because the data belong to the School of Public Health of Fudan University. However, they are available from the corresponding author upon reasonable request.
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Acknowledgements
The authors thank all the participants of this study and all members involving the collection of the baseline data.
Funding
All phases of this study were supported by High-level Talents Scientific Research Start-up Fund of Hainan Medical University, 2019 (XRC190011); 2020 Graduate Innovative Research Project of Hainan Medical University (HYYS2020-32).
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SW and QW participated in the field investigation phase, and drafted the report. JZ and ZY conceived and designed the study, and investigated and revised the manuscript. BZ did the statistical analysis. YH, SF and DY contributed to data collection, analysis, and interpretation. All authors revised the report and approved the final version before submission.
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This study has been approved by the Ethics Committee of Hainan Medical University (No.:HYLL-2022-244), all parents and class teachers of the children under investigation have signed written informed consent.
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Wang, S., Wu, Q., Hu, Y. et al. Indoor environmental factors and pneumonia in preschool children in Haikou China. Sci Rep (2026). https://doi.org/10.1038/s41598-026-42519-7
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DOI: https://doi.org/10.1038/s41598-026-42519-7
