Abstract:
Background: Household air pollution is among the top ranked global public health concern particularly in developing nations, like Africa. Eighty percent of the population of sub-Saharan Africa and 90% of the Ethiopian population use biomass fuels for cooking. It is linked to many health problems including acute respiratory infection in children. The cause of this health problems is attributable to many factors including household air pollution. Acute respiratory infection is the most common illnesses in childhood, comprising as many as 50% of all illnesses in children less than 5 years old in the world. Household air pollution is still a big problem in developing countries. In Ethiopia, pneumonia alone contributed to 27% of all illness and 18% of all deaths to under-five children. Exposure assessment on indoor air pollution, specifically linked to acute respiratory infection is limited in Ethiopia. Objective: To assess household air pollution and its health effects among under-five age children in Wolaita Sodo town, Ethiopia. Methods: A community-based unmatched case-control and cross-sectional study design were used in the study. Census has been conducted prior to the actual data collection to specify sampling frame. One thousand one hundred forty-four (1144) children with cases to controls ratio of 1:3 (i.e. 286 cases and 858 controls) aged 0-59 months paired with their mothers were participated in the study. Cases are defined as a child who fulfilled the world health organization criteria of acute respiratory infection (i.e. a child who suffered from cough, followed by rapid breathing in the two weeks that preceded the survey date), while controls are a child who is free of any complaints of respiratory illnesses in the two weeks that preceded the survey date. In an eleven Kebele (the smallest administrative structure/unit of the government) in the town, six Kebeles were selected randomly. Sample sizes were distributed based on probability proportional to size of the households in each Kebele. Census of all children in the selected Kebeles were conducted to set the sampling frame. Based on the sampling frame, cases and controls of acute respiratory infection in a child were identified using case definition of acute respiratory infection by interviewing their mothers. The mother of a child was interviewed about her child health history for assessment of cases and controls. For exposure assessment, a sub sample of 110 kitchens and 66 were involved to determine the level of particulate matter (PM 2.5 ) and carbon monoxide pollution respectively from biomass fuel XII using a monitoring equipment designed by the University of California, Berkeley Particle Monitor (UCB-PM) and HOBO CO data logger, respectively. Data were managed and analyzed using Epi Info and SPSS version 21. Exposure data were managed using UCB Monitor Manager software (Version 2.1.3) and BoxCar Pro software (Version 4.3) software. Descriptive statistics, Odds ratio, Chi-squired tests, Unconditional logistic regression, Linear regression, ANOVA, Pearson's correlation coefficient and Eta-test were employed. Results: The study was conducted with the response rate of 99.65%. The mean age of the children was 24.15 (SD=14.98) months, while the age group between 12-23 months was accounted to 330 (28.86%). More than three-fourth of children lived in households that used mainly polluting fuel for cooking, biomass fuel 1001 (87.5%), while the rest only 143 (12.5%) of the households used mixed type of fuel energy, such as biomass, electricity, biogas and liquefied petroleum gas. About 712 (62.23%) of households had a kitchen separated from the main house, while 351 (30.68%) of the households had kitchen inside the living house. About 417 (58.5%) of the kitchen had no chimney, 666 (93.54%) didn’t open windows during the cooking time. The prevalence of acute respiratory infection in under-five children were 10.1% (95% CI 9.5, 10.8). Biomass fuel users for cooking (AOR=2.08, 95% CI 1.03-4.22), poorly ventilated houses (AOR=4.31, 95% CI 2.60-7.15), less than 2 years of child birth interval (AOR=1.40, 95% CI 1.021.91), large family size, (AOR=1.85, 95% CI 1.30-2.61), petty trade job of mother (AOR=0.50, 95% CI 0.31-0.81) were significant risk factors of acute respiratory infection in under five children. A 24 hour Geometric mean concentration of PM 2.5 in all monitored households were 413.27 µg/m 3 . The arithmetic mean 772.03 µg/m 3 (837.39) with 95% CI 613.04, 931.01. The 24 hour measurement of mean concentration of carbon monoxide in all monitored households were 14.26 mg/m 3 (SD=10.06). Type of fuel use, type of stoves (improved/traditional) and duration of time spent in cooking had significant differences on the level of particulate matter and Carbon monoxide. Conclusions: The prevalence of acute respiratory infection is still a public health concern given the high level of household air pollution. Biomass fuel sources and poor house ventilation had a significant association on acquiring of acute respiratory infection. Mother’s unemployment, higher family size, child birth interval of less than 2 years, biomass fuel use for cooking, living a poor ventilated house and carrying child while cooking were risk factors of acute respiratory infection among children. The geometric mean concentration of particulate matter and carbon monoxide were much more exceeded the World Health Organization Air Quality Guideline values. Recommendations: Promotion and distribution of improved cooking stoves, introducing better house design, promote a separate kitchen, to incorporate a sufficient number of windows and rooms in the house are sustainable solutions. Health education and promotion on the preventive measures of acute respiratory infection, the risk of biomass fuel combustion and engaging or carry child in the back while cooking and the importance of house ventilation should be delivered. Sustainable urban electrification (clean energy supply) is highly recommended solution to solve the cooking fuel related health problems.