A main research goal for the Hub is to assess the impact of outdoor air pollution on children’s health. Urban air pollution affects the respiratory health of school children with contributions to exposure varying widely across different micro-environments including home, on the road to school and in school compounds. Because of the substantial time spent at school, elementary schools are useful study settings to recruit students, and enroll and follow them to assess for chronic health effects from exposure to air pollution.
Cycle I (2016-2022)
Building on the rich history of the Southern California Children’s Health Study, one of the largest and most detailed studies of the long-term effects of air pollution on the respiratory health of children, a cross-sectional study (one time sampling) using a similar approach was conducted in Addis Ababa, Ethiopia; Kampala, Uganda; and Nairobi, Kenya, hereafter known as the Eastern Africa Children’s Health (EACH) study. EACH studies were initiated in a phased approach in each country by researchers from Addis Ababa University, Ethiopia; Makerere University, Uganda; and University of Nairobi, Kenya for a period of one year between 2016-2020 using common protocols and study designs.
The goals of the EACH study are (1) to determine the effects of outdoor and biomass-derived PM2.5 exposure on attained levels of lung function in children, and respiratory symptom morbidity; (2) to determine the dose-response relationships with outdoor pollution; and (3) to determine personal exposure to PM2.5 via spatio-temporal modeling techniques whenever it is possible to assess and estimate personal PM2.5 exposure using microenvironmental models.
Each country team enrolled and assessed respiratory health in 1000-1100 9-10 year old children recruited from schools in 10 districts from each capital city representing contrasting levels of indoor and outdoor air pollution (PM2.5). These locations were selected to have similar climate, elevation and social characteristics in each country. Outdoor PM2.5 exposure was measured at each of the 10 school for a 10-12 month period using Met One Inc. E-Samplers. Participant health assessments included lung function performance measured using computerized spirometry, and a detailed questionnaire to assess health history, a housing survey including indoor exposure sources, and a spatial and physical time-activity survey.
Recognizing the need for more detailed data on indoor pollution exposure from the use of biomass fuel for cooking, lighting and heating, a sub-study of the EACH study, the Household Air Pollution Study, was conducted to assess household level PM2.5 and black carbon levels in 30% of EACH study participants in Ethiopia.
Cycle II (2022-2026)
Building on the model provided by the Southern California Children’s Health Study,6 and on the Cycle I EACH studies, researchers in Ethiopia, Uganda and Kenya will re-enroll participants from Cycle I to collect follow-up data in Cycle II. The follow-up EACH Study will be initiated in a phased approach at each study site by Hub researchers from Addis Ababa University, Ethiopia; Makerere University, Uganda; and University of Nairobi, Kenya for a period of one year between 2023-2026 using common protocols and study designs. Health assessments will include lung function performance measured using computerized spirometry, health assessment questionnaire, housing survey including indoor exposure sources, and a spatial and physical time-activity survey. Outdoor school-based pollution monitoring will be sustained for three years to provide stable long-term averages for exposure estimation using MODULAIR-PM monitors. The MODULAIR-PM monitors will be deployed at the 30 schools that were sampled in Cycle I (10 per city). Three units per city will also be outfitted with carbon monoxide (CO), ozone (O3), nitrogen oxide (NO) and black carbon monitors which will enable researchers to estimate source apportionment (source specific contributions to outdoor air pollution). The addition of longitudinal follow-up will allow research teams to assess lung function development trajectories. Common protocols for the EACH study will enable pooled analyses to provide regional policy relevant evidence.
The EACH studies will serve as the basis for many of the sub-studies to be conducted as part of the Hub’s program of research including the Personal Air Pollution Exposure and Mothers’ Health studies in Ethiopia, Uganda and Kenya, the Ambulatory Blood Pressure Study in Uganda, and the Cognitive Performance Assessment Study in Kenya.