Impacts of Air Pollution on Pediatric Respiratory Infections Under a Changing Climate in Mombasa, Nairobi and Nakuru Cities

Abstract

As climate keeps on changing mainly due to anthropogenic causes, almost all sectors are likely to face impacts in one way or another. The health sector is more sensitive to the changing climate, which will affect those most vulnerable, more so children, especially in developing countries. Acute respiratory infections affect children partly due to their small nature and still undeveloped respiratory systems, making climate change a serious threat to their lives. Atmospheric pollutants appear to contribute much in respiratory infections, where they have an effect on spreading viruses and bacteria. This study aimed to assess the impacts of air pollution on pediatric respiratory infections under a changing climate in Mombasa, Nakuru, and Nairobi cities. The data used in this study was open-source: Air pollutants, comprising of particulate matter, sulphur dioxide, carbon monoxide and ozone; and climate data, comprising of minimum temperature and rainfall, were obtained from satellite, through the Modern-Era Retrospective analysis for Research and Applications, version 2 (MERRA-2) from 1990 to 2020. Minimum temperature was used in this study as a climate change indicator. Pediatric lower respiratory data was obtained from the Institute of Health Metrics and Evaluation (IHME) from the University of Washington, ranging from below 1 to 14 years for periods of 1990 to 2019, constituting of the number of morbidities and mortality cases for the three towns under study. The methods used in order to obtain results were: Mann-Kendall test, to check for trends in atmospheric pollutants and climate parameters, multicollinearity to test for correlation of air pollutants and climate parameters, and a multiple regression analysis to find out the relationship between pollutants and morbidities and mortalities. Results from the study pointed out that air pollutants: PM2.5, carbon monoxide, sulfur dioxide and tropospheric ozone were all increasing over the study period in all three cities. Minimum temperature was also found to be increasing, while precipitation increased in all cities except Mombasa where it shown a steady decline over the 30-year period. Morbidity and mortality cases showed a decrease from 2010 iv onwards for children below 4 years, while the numbers increased for children above 5 years. PM2.5, carbon monoxide, sulfur dioxide had a direct impact on morbidities and mortalities of lower pediatric respiratory infections in all towns. The rising minimum temperatures observed in Mombasa, coupled by reduced precipitation enhanced the spread of air pollutants, more so particulate matter increasing morbidity cases in the city. Nakuru was observed to have the highest precipitation rates in all three cities, which created a ‘washing effect’ for most pollutants in the air while at the same time having a ‘blanket’ effect on carbon monoxide hence higher values. Nairobi also had high levels of carbon monoxide, sulfur dioxide and black carbon for PM2.5, which mostly came from the high number of motor vehicles. Lower pediatric respiratory infections are then expected to increase mainly due to the presence of rising particulate matter (2.5) values in the atmosphere, under which the influence of climate change will enhance its spread and dispersion in various areas, posing huge threats on the current and next generation of children. Seasonal variation of climate variables will also have an impact on lower pediatric respiratory infections, increasing and decreasing their cases annually. The study recommends the use of this information for strengthening policy making in health, transport and industrial sectors, which will enable the reduction of pollution effects on children who are the most vulnerable in the population.