Respiratory infections among junior high school students in upper northern Thailand: The role of building dampness and mould, biomass burning and outdoor relative air humidity (RH)

Tippawan Prapamontol; Dan Norbäck; Nathaporn Thongjan; Neeranuch Suwannarin; Kawinwut Somsunun; Pitakchon Ponsawansong; Kesseya Radarit; Sawaeng Kawichai; Warangkana Naksen

doi:10.1016/j.envres.2023.116065

Respiratory infections among junior high school students in upper northern Thailand: The role of building dampness and mould, biomass burning and outdoor relative air humidity (RH)

Environ Res. 2023 Aug 15;231(Pt 1):116065. doi: 10.1016/j.envres.2023.116065. Epub 2023 May 4.

Authors

Tippawan Prapamontol¹, Dan Norbäck², Nathaporn Thongjan³, Neeranuch Suwannarin³, Kawinwut Somsunun³, Pitakchon Ponsawansong³, Kesseya Radarit³, Sawaeng Kawichai³, Warangkana Naksen⁴

Affiliations

¹ Research Institute for Health Sciences, Chiang Mai University, Chiang Mai, Thailand; Environmental and Occupational Health Sciences and Non-Communicable Diseases Center of Excellence, Chiang Mai University, Chiang Mai, Thailand.
² Research Institute for Health Sciences, Chiang Mai University, Chiang Mai, Thailand; Department of Medical Sciences, Uppsala University, Uppsala, Sweden. Electronic address: dan.norback@medsci.uu.se.
³ Research Institute for Health Sciences, Chiang Mai University, Chiang Mai, Thailand.
⁴ Faculty of Public Health, Chiang Mai University, Chiang Mai, Thailand.

PMID: 37149023
DOI: 10.1016/j.envres.2023.116065

Abstract

Background: Few studies exist on environmental risk factors for respiratory infections in Thai school children.

Aim: To study associations between home and outdoor environment and respiratory infections among school children in Northern Thailand in dry and wet season.

Methods: A repeated questionnaire survey among the children (N = 1159). Data on ambient temperature and relative air humidity (RH) and PM₁₀ and ozone was collected from nearby monitoring stations. We used logistic regression to calculate odds ratios (OR).

Results: 14.1% had current respiratory infections (last 7 days), 32.1% had any respiratory infection last 3 months, and 26.1% had any respiratory infection last 12 months with antibiotic treatment. Students with diagnosed allergy (7.7%) and diagnosed asthma (4.7%) had more often respiratory infections (ORs 1.40-5.40; p < 0.05). Current respiratory infections were more common in dry (18.1%) than in wet season (10.4%) (p < 0.001) and was associated with indoor mould (OR 2.16; p = 0.024) and outdoor RH (OR 1.34 per 10% RH; p = 0.004.) in the total material. In wet season, mould (OR 2.32; p = 0.016), window pane condensation (OR 1.79; p = 0.050), water leakage (OR 1.82; p = 0.018), environmental tobacco smoke (ETS) (OR 2.34; p = 0.003) and outdoor RH (OR 2.70 per 10% RH; p = 0.01) were risk factors for current respiratory infections. In dry season, mould (OR 2.64; p = 0.004) and outdoor RH (OR 1.34 per 10% RH; p = 0.046) were associated with current respiratory infections. Irrespectively of season, biomass burning inside or outside the home was a risk factor for respiratory infections (ORs 1.32-2.34; p < 0.05). Living in a wooden house decreased the risk of respiratory infections (OR 0.56: p = 0.006).

Conclusions: Dry season, high outdoor RH, household dampness, indoor mould and ETS can increase childhood respiratory infections. Living in a traditional wooden house can reduce respiratory infections, possibly due to better natural ventilation. Smoke from biomass burning can increase childhood respiratory infections in northern Thailand.

Keywords: Biomass burning; Dampness; Home environment; Indoor mould; Respiratory infections; Wooden house.

MeSH terms

Air Pollution, Indoor* / analysis
Biomass
Child
Fungi
Humans
Humidity
Respiratory Tract Infections* / epidemiology
Students
Thailand / epidemiology
Tobacco Smoke Pollution*

Substances

Tobacco Smoke Pollution