Respiratory symptoms and fractional exhaled nitric oxide (FeNO) among students in Penang, Malaysia in relation to signs of dampness at school and fungal DNA in school dust.
Few health studies exist on dampness and mould in schools in the tropics. We studied associations between fraction of exhaled nitric oxide (FeNO), respiratory symptoms and airway infections among students and dampness and fungal DNA in schools in Malaysia. A total of 368 randomly selected students from 32 classrooms in 8 secondary schools in Penang, Malaysia, participated (58% participation rate). Information on current respiratory symptoms and the home environment was collected by a standardised questionnaire. FeNO was measured by NIOX MINO (50ml/min). The classrooms were inspected and dust was collected by vacuuming on special filters and was analysed for five fungal DNA sequences by quantitative PCR. Linear mixed models and 3-level multiple logistic regression (school, classroom, student) were applied adjusting for demographic data and the home environment. Totally 10.3% reported doctor's diagnosed asthma, 15.1% current wheeze, 12.4% current asthma, 37.3% daytime breathlessness, 10.2% nocturnal breathlessness, 38.9% airway infections and 15.5% had pollen or furry pet allergy. The geometric mean of FeNO was 19.9ppb and 45% had elevated FeNO (>20ppb). Boys had higher levels of FeNO. Chinese had less daytime breathlessness than Malay (OR=0.30: p<0.001). Indoor carbon dioxide levels were low (380-720ppm). Dampness was observed in 18% of the classrooms and was associated with respiratory infections (OR=3.70; 95% CI 1.14-12.1) and FeNO (p=0.04). Aspergillus versicolor DNA was detected in 67% of the classrooms. Higher numbers of Aspergillus versicolor DNA in classroom dust were associated with wheeze (p=0.006), current asthma (p=0.002), respiratory infections (p=0.005) and elevated FeNO levels (p=0.02). In conclusion, respiratory symptoms were common among the students and the high FeNO levels indicate ongoing airway inflammation. Building dampness and the mould Aspergillus versicolor in schools in Malaysia can be risk factors for impaired respiratory health among the students.
Uppsala University, Department of Medical Science, Occupational and Environmental Medicine, University Hospital, 75185 Uppsala, Sweden. Electronic address: dan.norback@medsci.uu.se.
Dan
D
Norbäck
United Nations University-International Institute for Global Health, 56000 Kuala Lumpur, Malaysia; Department of Community Health, National University of Malaysia, 56000 Kuala Lumpur, Malaysia.
Jamal Hisham
JH
Hashim
Department of Environmental and Occupational Health, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
Zailina
Z
Hashim
Uppsala University, Department of Medical Science, Occupational and Environmental Medicine, University Hospital, 75185 Uppsala, Sweden.
Gui-Hong
GH
Cai
Department of Community Health, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
Vinoshini
V
Sooria
Department of Community Health, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia; Environmental Health, Allied Health Science College Sg Buloh, Ministry of Health Malaysia, 47000 Sungai Buloh, Selangor, Malaysia.
Syazwan Aizat
SA
Ismail
Uppsala University, Department of Medical Science, Occupational and Environmental Medicine, University Hospital, 75185 Uppsala, Sweden.
Gunilla
G
Wieslander
D000293:Adolescent; D016902:Air Pollution, Indoor / Q000032:analysis*; D001249:Asthma / Q000453:epidemiology*; D004271:DNA, Fungal / Q000032:analysis*; D004391:Dust; D005260:Female; D006801:Humans; D008296:Malaysia; D008297:Male; D009569:Nitric Oxide / Q000032:analysis*; D012135:Respiratory Sounds; D012574:Schools; D013334:Students
D004271:DNA, Fungal; D004391:Dust; D009569:Nitric Oxide
Asthma; Building dampness; Children; Fungal DNA; Mould; School environment