we present an array of researchers who conducted scientific studies on childhood diarrhea and childhood mortality worldwide by focusing on the linkage between sanitation practices indicators and under five diarrheas as well as its effect on child mortality. Some key terms are: Under five children: Living children not yet celebrating their fifth birth day; Under-five mortality: the probability of a child dying before reaching the age of five year; Infant mortality: the probability of a child dying before his or her first birthday (UN, 2013); Diarrhea: According to the World Health Organization (WHO, 2013), diarrhea is “the passage of three or more loose or liquid stools per day, or more frequently than is normal for the individual.” If left untreated, diarrhea can lead to severe dehydration, which can result in hospitalization or even death.
2.1. Environmental factors of childhood diarrhea prevalence
Poor environmental infrastructure is associated with poor sanitation practices(Genser, Strina, Prado, Barreto, & Cairncross, 2008) , (O Connell, Quinn, & Scheuerman, 2017) and (Mohammed & Zungu, 2016). Mohammed and his colleague tried to investigate the Socioeconomic factors associated with diarrheal diseases among under-five children of the nomadic population in northeast-Hadaleala District of Ethiopia using cross-section data collected for 704 under-five children and analyzed using multivariable logistic regression method to identify socioeconomic variables associated with childhood diarrhea and revealed four variables that are protective factors for childhood diarrhea: type of toilet facility(Un improved/improved), availability of specific hand-washing places(available/not available), availability of hand-washing facilities(available/not available) and mothers’ knowledge on diarrhea causation(poor/good). This was confirmed by (Uwizeye, okoni, & Kabiru, 2014) in their study correlates of diarrhea in MATYAZO cell of HUYE town in Rwanda and found that being far from roads, poor sanitation and rainy seasons increases the likelihood of being infected by diarrhea among peoples in all ages. Un like them, not only (O Connell et al., 2017) who analyzed the RDHS2010 and concluded that the childhood diarrhea prevalence is independent on type of Water Source and type of sanitation facility in Rwanda but also (Sinharoy et al., 2016) in their study where they tried to explore the associations of environmental and demographic factors with diarrhea and nutritional status among children in Rusizi district of Rwanda using cross-sectional data collected for 8847 households and analyzed using Log-binomial regression models and concluded also that the treatment of drinking water (any method) is inversely associated with caregiver-reported diarrhea in the previous 7 days (PR = 0.79, 95% CI: 0.68–0.91) and this is differs of what (KIMANI, 2013) found in his study. His study concluded that water treatment did not have any association with childhood diarrhea.
Moreover, (Danquah, Mensah, Agyemang, & Awuah, 2015)in their study where they investigated risk factors associated with diarrhea morbidity among children younger than five years in the atwimanwabiagya district of Ghana using cross section data collected in dry season on 378 households supported what Mohammed and his colleague which is the same for sinharoy and colleagues found in Rwanda by concluding that type of toilet facility (public / private) is independent of childhood diarrhea prevalence in that region. The former added also that the disease is independent on the distance to water source.
2.2. Socio-Demographic factors of childhood diarrhea prevalence
Socio-demographic factors are taken as the proximate determinants of childhood diarrhea prevalence as pointed by many researchers for instance (Ganguly, Sharma, & Bunker, 2015) their meta analysis, the investigated the Prevalence and risk factors of diarrhea morbidity among under-five children in India using a systematic review of comprehensive electronic search of relevant medical subject heading and revealed a significant association with anemia level of the child, and low socioeconomic status. Unlike other researchers; Age of the child (<24 months), mothers’ low literacy status and untreated drinking water did not show a significant association. Sex of the child, religion, higher education of mothers, and seasonality were found to be inconsistently associated in single studies. This is not the same for (O Connell et al., 2017) in their study where they tried to investigate the Risk factors of diarrheal disease among children in the East African countries of Burundi, Rwanda and Tanzania using Demographic and Health Surveys (DHS) Program Data on child health in those countries from 2010 using simple and multiple logistic regressions to identify predictors of diarrhea and concluded that young mothers, and the mother’s education level (secondary school or less) have a very significant association with childhood diarrhea prevalence considering both Burundian and Rwandese children. It further revealed that unlike in the Burundi, seasonality in favor of rainy season increases the likelihood of being infected in the other countries.
This goes in line of what Mohammed and his colleague found where they concluded that Age( in favor of 6-11 months; 12-23 months; 24-35 months) of child, number of children below five-years ( in favor of 2 and 3 children), and mother education level (Illiterate mothers) were found to be associated with childhood diarrhea prevalence. Unlike them (Danquah et al., 2015) didn’t found any significant childhood association considering number of under five children in a household but confirmed its association with mother’ age and mother’ education level.
2.3. Socio-economic factors of childhood diarrhea prevalence
Poor socioeconomic increases diarrhea risk, mostly mediated by lack of sanitation, poor infrastructure and living conditions (Genser et al., 2008). This is because it is difficult for poor families to afford improved sanitation practices and higher education as the perquisite in terms of awareness or accessibility. In their study of the impact of sanitation practices on childhood diarrhea, (Genser et al., 2008) concluded that a sanitation intervention in a given infected population can have a substantial impact on the epidemiology of child diarrhea. Improving sanitation decreases the attributable risk of diarrhea determinants directly by reducing exposure to these factors, or indirectly by changing the strength of associations with them. This is confirmed by (Ngabo et al., 2016) in their study of the economic burden of childhood diarrhea in Rwanda. They found that Households often bear the largest share of the economic burden attributable to diarrhea hospitalization and the burden can be substantial, especially for households in the lowest income quintile. The same findings for (Mohammed & Zungu, 2016) who found also that household wealth (poor households) has a positive association with childhood diarrhea. This differs from what (O Connell et al., 2017) found by considering different population of Rwanda, Burundi and Tanzania. The associated were confirmed only for Rwandese children.
2.4. Childhood diarrhea and childhood mortality
Untreated diarrhea can kills peoples especially younger children. When a person gets diarrhea, the body begins to lose a lot of water and salts or electrolytes (sodium, chloride, potassium and bicarbonate). They are normally lost through liquid stools, vomit, sweat, urine and breathing, they are all necessary for life but if the water and salts are not replaced fast, the body starts to "dry up" or get dehydrated. Severe dehydration can cause death especially for children less than five years of age (Nasser, 2014). It is the second leading cause of morbidity and mortality worldwide (WHO, 2017a) and the third leading cause of under five morbidity and mortality in Rwanda (MOH, 2014). The developing countries especially the ones from sub Saharan Africa have the biggest share of the world’s total deaths due to diarrhea (98.7% and 49.6% respectively)(UNICEF et al., 2015).
Some authors concluded that it even kills than HIV and malaria when combined (Centers for Disease Control and Prevention, 2014). This center further reported that diarrhea causes stunting and wasting as well as cognitive development. On the other hand Some researcher did not show any significant association between diarrhea and mortality. For example (Simms, Milimo, & Bloom, 1993) analyzed the reasons for the rise in unde-five mortality but he found that for the same period the under-five diarrhea prevalence were decline.
This research is based on (Mosley & Chen, 1984) theoretical framework to reach its objectives. Though this model was conceived to point out determinants of under-five mortality, it has been a standard instrument in analyzing and understanding under-five mortality. Mosley and Chen’s model consolidates both socioeconomic and proximate factors as main determinants of under-five children’s mortality. Biological factors are considered as direct factors whereas socioeconomic factors are considered as indirect factors in their conceptual framework.
They enlarged Chen’s framework by grouping determinants of under-five mortality into 5 categories relating to (1) environmental contamination, (2) maternal factors (3) nutrient availability, (4) injuries and (5) disease control. They grouped these factors into direct and indirect risk factors.
The direct factors comprise a) maternal factors (age at birth, parity, and birth intervals), b) nutrient deficiency factors (nutrient availability to the infant and to the mother during pregnancy and lactation), c) injuries (recent injuries or injury-related disabilities), d) environmental contamination factors (intensity of household crowding, water and food contamination, housing conditions, energy availability…), e) personal illness control (use of preventive services as immunizations, malaria prophylactics or antenatal care, and use of curative measures for specific conditions).
The indirect factors are made of a) Individual level factors (skills, health and time, usually measured by mother’s educational level, tradition/norms/attitudes, beliefs about disease causation…), b) Household level factors (food availability, clothing, transportation, daily hygienic and preventive care, access to information…), c) Community level factors (climate, temperature, altitude, season, rainfall, health system variables…).
In this perspective, Mosley and Chen’s following conceptual model enlightened my path to the formulation of the hypothesis and problem statement as shown in Figure 5:
Mosley and Chen here above show us how under-five mortality phenomenon is caused by an aggregate of risk factors. Proximate and socioeconomic determinants interact and lead to under-five mortality. Environmental, nutrient deficiency factors associated with maternal, personal illness control and injury related factors affect positively or negatively a child by giving him a healthy and sickness status. The sickness status could be a cause of a child’s growth faltering or death. Direct determinants are directly linked to child survival whereas socioeconomic or indirect factors influence under-five mortality when they are combined with the first one.
However this modifies the model to fit the available variables in the RDHS2015 database file. This study excludes nutrient deficiency and injury factors mentioned in Mosley and Chen's model because the RDHS 2015 did not collect such information at the time of the survey. It also eliminates personal illness control in form of diarrhea treatment/ oral rehydration therapy because the focus of the study is to determine the risk factors associated with childhood diarrhea and not the diagnosis platform. Thus, in this study variables were regrouped into: socio-economic, socio-demographic and environmental variables.
a) Social economic status: These include the mother’s education levels, marital status and the household’s income levels.
b) Environmental factors: These factors include sanitation and living conditions for example sewerage systems, source of water supply, nature and type of toilets as well as both household and personal hygiene behavior.
c) Socio-demographic factors: These factor include age and gender of the child’s care giver respectively. Like in the mosley and chen model, both environmental factors and socio-demographic factors are the proximate determinants of childhood diarrhea whereas socio-economic factors are taken as effect modifiers.
The main concepts in this model are subdivided into: Environmental factors: These include Household Living condition variables (those variables will help us to know the level of hygienic practices in households) and Infrastructure and sanitation variables (Those variables will help us to assess the household’s neighboring infrastructure that could affect the health of the child). Socio-Demographic Factors: These variables indicates disparities among different level of demographic factors and Include age of the child, mother’s education level, number of siblings below five years in a household and seasons. Socio-economic variables: these variables indicate the affordability of hygienic practices and include the place of residence and wealth index. These factors are operating through the direct factors as effect modifiers.