Association Between Specific Indoor Air Pollutants and Pneumonia Episodes in Children Under Five in Abuja, Nigeria: A Case-control Study

Abstract Background: Pneumonia causes most death in children under five globally. Indoor air pollution has been reported to increase the risk of children to pneumonia. Objective To investigate the association between specific indoor air pollutants and pneumonia episodes in children under five. Methods Using a case-control study design, we compared exposure of cases and controls to specific pollutants (PM 2.5 , CO, BC and PM 1 ), using battery operated aerosol monitors. Data was analysed using Wilcoxon signed-rank test. Results The mean PM 2.5 was higher in controls compared to cases. PM 2.5 highest mean recorded for controls was 177 µg/m 3 . There was a significant difference between cases and controls for 10 hours ( p- value 0.0147), 15 hours ( p- value 0.0111) and 20-24 hours ( p- value 0.0296) for PM 2.5 . No significant difference in CO concentration between cases and controls, the highest CO mean concentration recorded being 2930 µg/m 3 . Similarly, PM 1 was consistently higher in controls compared to cases. However, this difference was not significant from exposure to PM 1 between cases and controls ( P- value>0.05), with the highest PM 1 mean concentration recorded being 91 µg/m3. There was a significant difference ( p- value 0.0260) in exposure to Black Carbon between cases and controls. BC was higher in households of cases compared to controls, with the mean average of BC for cases 4350 µg/m3 and controls 4126 µg/m3. In this study, BC is positively associated with a pneumonia episode. We also report the importance of unmodifiable and behaviourally modifiable factors on pneumonia episode in children. Discussion: In conclusion, we show that children present during cooking, number of available windows and MUAC increased the likelihood of a pneumonia episode. We recommend household level behaviour changes and targeted IMCI including early effective detection and treatment of childhood pneumonia particularly in high pollution areas in Nigeria.