The nexus between household water insecurity, mother's handwashing practices, and diarrheal diseases among under-five children

Diarrheal diseases are still a major cause of illness and death among children under the age of five in developing countries (Ahs et al. 2010). According to the World Health Organization (WHO), there are approximately 2.5 billion cases of diarrhea among children under the age of five worldwide each year, with most of these cases occurring in Southeast Asia and sub-Saharan Africa (WHO 2009). An updated analysis focusing on low- and middle-income countries verified that 60% of diarrheal deaths are caused by inadequate drinking water, sanitation, and poor hygiene (WASH) (Prüss-Ustün et al. 2019). Recent evidence from a systematic review and meta-analysis in Ethiopia also verified that diarrheal diseases were a major contributor to under-five death in the country (Alebel et al. 2018). Handwashing with soap at five key times was the most cost-effective method to prevent childhood diarrhea (Hashi et al. 2017). Several studies have also demonstrated that washing hands with soap is crucial for interrupting pathogen transmission and preventing diarrhea (Taddese et al. 2020; Noguchi et al. 2021).

However, insufficient domestic water supply can lead to poor hygiene practices (Oswald et al. 2008; Howard et al. 2020). Findings obtained from Burundi and Peru proved that handwashing frequency is affected by the amount of water available per person in households (Gilman et al. 1993; Seimetz et al. 2016). A study conducted in Debark town, Ethiopia, also found that the availability of water in the households, as well as the knowledge and attitude of mothers, significantly affects handwashing practices (Dagne et al. 2019). Inadequate access to water can also be associated with water insecurity, which could reduce hygienic practices and increase the risk of water-related diseases (Howard et al. 2020).

A study conducted in Ethiopia indicated that water insecurity was linked to an increase in the distance to the water source and a decrease in the quantity of water available in households (Stevenson et al. 2012). It is a critical problem that is associated with a decrease in hygiene practices and an increase in the incidence of childhood diarrhea (Nounkeu et al. 2019). Evidence obtained from rural Ethiopia also indicated that an increase in water insecurity was associated with an increased occurrence of childhood diarrhea (Hadley & Freeman 2016). Water insecurity refers to the inability to access and benefit from water that is adequate, affordable, reliable, and safe for maintaining a healthy life (Jepson et al. 2017). Inadequate water supply was also responsible for various water-related diseases in Hosanna town, particularly in the peri-urban and informal settlements. Peri-urban areas are located on the outskirts of the town and typically consist of legal settlements. However, in some cases, there may be illegal settlements on private land within these areas. These settlements often lack proper access to essential services like water and sanitation. Informal settlements, on the other hand, are situated in the transition zone between the urban periphery and rural areas. These settlements lack formal land tenure rights and are predominantly illegal. They suffer from inadequate infrastructure, including roads, electricity, and water supply (Aydamo et al. 2023). Therefore, it is crucial to examine how water insecurity affects mother's handwashing practices and childhood diarrhea and their links in the study area.

Mothers play a critical role in their children's health, and improving their knowledge, attitude, and practices can improve children's health (Workie et al. 2018). The role of handwashing with soap in preventing diarrheal diseases has been extensively studied worldwide. However, there is little information on the relationship between household water insecurity (HWIS), mother's handwashing practices, and the prevalence of childhood diarrhea. Therefore, the objective of this study was to examine the association between HWIS, mother's handwashing practices, and childhood diarrhea in the peri-urban and informal settlements of Hosanna town. The information obtained from this study could serve as baseline information for improving household water security, mother's handwashing practices, and child health in the study area.

A community-based cross-sectional study was conducted from April 21, 2022 to May 27, 2022.

The calculated sample size was 384, and adding 10% non-response, the total sample size for this study was estimated to be 424. The study was carried out in Hosanna town, specifically in three kebeles, namely Bobicho, Sech-Duna, and Jelo-Naremo kebeles. These kebeles were selected purposively because they have a significant number of peri-urban and informal settlements. Kebele is the lowest governmental administrative structure in Ethiopia. Mothers were allocated proportionally into these kebeles based on the size of each kebele. Then, simple random sampling techniques were employed to select mothers participating in the study from the selected kebeles. The sampling frame was under-five children aged between 0 and 59 months.

The study included mothers/caregivers who had lived in the peri-urban and informal settlements of the selected kebeles for at least 6 months and had at least one child under 60 months of age during the study period. On the other hand, mothers who had lived in the area for less than 6 months were excluded from the study. This is because the mothers who had lived in the area for less than 6 months were less likely to provide adequate information about the study as they were less familiar with the local environment and resources available. Additionally, they were more likely to have recently migrated to the area, which can make it difficult to track down and interview them. The exclusion of these mothers from the study ensured that the results were not biased by the fact that they were less likely to provide adequate information about the study.

The data were gathered using a pretested structured questionnaire, the HWISE Scale, and an observational checklist. The questionnaire was first created in English and then translated into Amharic. The translated version was then translated back into English to ensure its accuracy. The pretesting was conducted on 5% of the sample size to check the quality of the questionnaire, and feedback obtained from the pretesting was incorporated into the questionnaire. Data were collected by trained health professionals, and the data collection was monitored strictly to ensure that it was being conducted in accordance with the established procedures. The study collected data on diarrhea occurrences from the infant's mother or caregiver with a recall period of 2 weeks. The study evaluated the mother's handwashing at two separate practices, which are handwashing with soap and water, and water only. Mothers were asked about their handwashing practice with soap and water, and water only before feeding a child, after defecation, before eating food, after cleaning the child's bottom, and before preparing food to assess their handwashing practices at five critical times (Cronbach's alpha 0.80). Mothers who washed their hands with soap at each critical time were given one point, while those who did not were given zero points. Mothers who washed their hands with soap at more than three critical times were considered to have good handwashing practices, while those who washed their hands at less than three critical times were considered to have poor practices (Getahun & Adane 2021).

The study assessed the knowledge and attitude of mothers toward handwashing. The knowledge was evaluated based on the correct answers to 10 questions about handwashing (Cronbach's alpha 0.82). Then, a value of 1 was given for correct answers, and a value of 0 for incorrect or do not know responses. Households who scored above the mean knowledge score were considered as having good knowledge (Asekun-Olarinmoye Esther et al. 2014; Agaro et al. 2022). The attitude was assessed using seven questions on a Likert-type scale (Cronbach's alpha 0.75). This Likert scale has four items, which include strongly disagree, disagree, agree, and strongly agree in the questions. The responses were then divided into two categories, positive and negative attitudes. For positive attitudes, 1 point was given, while for negative attitudes, 0 points were given. Households that scored above the mean attitude score were considered to have a positive attitude, while households that scored below the mean attitude score were considered to have a negative attitude (Asekun-Olarinmoye Esther et al. 2014).

The HWIS was measured using the 12 items Household Water InSecurity Experiences (HWISE) Scale (Cronbach's alpha 0.86). A four-week-recall period was used to measure a household's water insecurity. The study participants were asked to reflect on 12 items on how frequently they or any household members experienced problems with water in the last 4 weeks (Young et al. 2019). The 12 items include worry about inadequacy of water supply, interruption of water supply, inability to wash hands after activities, take a shower, and wash clothes due to water-related problems. The items also include change of schedules to use water, change of food items, drinking water inefficiency, anger about water situation, thirst for water during sleep, a complete lack of useable or drinkable water, and feeling shame due to water-related issues (Supplementary Table S2). HWISE Scale scores were calculated by summing responses to each item and with possible total scores of 0–36, where higher scores indicate greater water insecurity. A cut-point of 12 was considered for defining water-insecure households, and households with an HWISE Scale score of 12 or higher are considered water insecure. Then, the proportion of water-insecure households was calculated by dividing the number of households with scores of 12 or higher by the total number of households.

The dependent variable of this study was the occurrence of childhood diarrhea with a recall period of 2 weeks (Yes or No), prevalence of HWIS, and handwashing practices at five critical times.

The independent variables predicting handwashing practices at five critical times and the occurrence of diarrhea were identified from the literature review. The factors that could predict handwashing practices at critical times include monthly HH income, mother's knowledge about handwashing, mother's attitude toward handwashing practices, water security status, maternal education, presence of handwashing facilities (HWF), availability of soap and water near HWF, maternal age, number of under-five children, marital status, mother's knowledge about handwashing practices at critical times, family size, and occupation of mothers. The factors that could predict diarrhea include diarrhea in the past 2 weeks in other household members, maternal age, monthly HH income, number of under-five children, vaccination status of the child, duration of breastfeeding, maternal education, age of child in months, handwashing practices at five critical times, handwashing practices (good vs. poor), water security status, sources of drinking water, sanitation facilities, solid waste disposal method, disposal of child's feces, covering of water storage container, types of drinking water storage containers, marital status, family size, occupation of mothers, breastfeeding status of the child, duration of water storage, and the presence of feces in the compound.

The study's data was analyzed using descriptive statistics, bivariate, and multivariable logistic regression models. Bivariate logistic regression was used to identify factors associated with diarrhea and mother's handwashing practices. It was used to determine unadjusted associations between independent variables and the outcome variables. On the other hand, a multivariable logistic regression model was conducted to identify factors associated with diarrhea and mother's handwashing practices by controlling for potential confounding factors. Variables scoring 0.25 in the bivariate analysis, which are moderately associated with the outcome variables, were included in the multivariable logistic regression analysis. The variance inflation factor (VIF) was calculated to check the presence of multicollinearity among independent variables. Model fitness was checked by calculating the log-likelihood ratio P-value and using the Hosmer–Lemeshow statistics. A variable scoring a P-value less than 0.05 was considered statistically significant. All quantitative data was analyzed using STATA 14 software.

• Handwashing practices at five critical times: It includes washing hands with soap before feeding a child, after defecation, before eating, after cleaning the child's bottom, and before preparing food.

• Diarrhea: It is defined as having at least three times or more loose or watery stools in 24 h period (WHO 2009).

• Water sources: It was categorized as either improved or unimproved based on WHO/UNICEF guidelines (WHO/UNICEF 2017).

• Sanitation facilities: It was categorized as either improved or unimproved based on WHO/UNICEF guidelines (WHO/UNICEF 2017).

• Disposal of children's feces: A child's stool was considered to be disposed of safely if a child uses toilet and puts/rinses feces in the toilet. Conversely, if feces were thrown into the garbage, left in an open area, or put/rinsed into a drain, it was considered unsafe (WHO/UNICEF 2006).

A total of 424 mothers who had at least one under-five child with a 100% response rate participated in the study. More than one-third of mothers attended primary schools (38.7%), and 88.9% of mothers were married. Three-fourths of the mothers (75.3%) were found in the 25–34 age category, and only 9.7% of mothers were exclusively breastfeeding their children during the data collection time. The majority of the children (58.7%) were partially vaccinated, while the remaining (41.3%) were fully vaccinated. Fully vaccinated children were those who received all the vaccines recommended for their age groups according to the Ethiopian national immunization program for tuberculosis, Hepatitis B, Hemophilus influenza type b, Polio, diphtheria, pneumonia, rotavirus associated gastro-enteritis, tetanus, pertussis, and measles (Wolde D et al. 2022; Wolde M et al. 2022). On the other hand, partially vaccinated children were those who have received one or two vaccines but have not yet completed the full vaccination series. The mean monthly income of the households living in the peri-urban and informal settlements of the town was 3503.7 ETB (Ethiopian Birr), which is lower than the other parts of the town (5452 Ethiopian Birr) (Teshale 2019). The mean monthly income of the households was also lower than the households living in other parts of Ethiopia, like Hawassa city and Wolkite town (Mekonen et al. 2022; Shitaye 2022). This is because a significant number of households living in the selected peri-urban and informal settlement areas were employed in low-skilled and low-paying jobs. Other socio-demographic and child-related factors are indicated in Table 1.

Thirteen independent variables, which include monthly HH income, mother's knowledge about handwashing, mother's attitude toward handwashing practices, water security status, maternal education, presence of HWF, availability of soap and water near HWF, maternal age, number of under-five children, marital status, mother's knowledge about handwashing practices at critical times, family size, and occupation of mothers that could predict handwashing practices at five critical times were identified from the literature. Then, the bivariate logistic regression analysis was conducted to identify factors associated with good handwashing practices at those times. The analysis revealed that maternal education at the secondary school level, good knowledge of handwashing, positive attitudes toward handwashing, household water security, the presence of HWF, the presence of water and soap near HWF, and being aware of five critical times to wash hands were significantly associated with good handwashing practices.

However, the multivariable logistic regression analysis showed that only good knowledge of handwashing, positive attitudes toward handwashing, household water security, and the presence of HWF were significantly associated with good handwashing practices. Mothers who had good knowledge of handwashing were four times more likely to have good handwashing practices compared with households having poor knowledge. A positive attitude toward handwashing practices was 13.6 times more likely to increase good handwashing practices compared with a negative attitude. The multivariate analysis also showed that water-secure households were four times more likely to have good handwashing practices compared with water-insecure households (Table 2). Water security can also improve the attitude of mothers toward handwashing practices. Around 82.7% of water-secure households had a positive attitude toward handwashing practices, while only 73.5% of water-insecure households had a positive attitude toward handwashing practices. The bivariate analysis verified that water-secure households were found to be 1.7 times more likely to have a positive attitude toward handwashing practices compared with water-insecure households (P-value < 0.05).

Around 27 explanatory variables predicting diarrhea were identified from the literature, which were considered in the bivariate analysis. These variables include factors like diarrhea in the past 2 weeks in other household members, maternal age, monthly HH income, number of under-five children, vaccination status of the child, duration of breastfeeding, maternal education, age of child in months, handwashing practices at five critical times, handwashing practices (good vs. poor), water security status, sources of drinking water, sanitation facilities, solid waste disposal method, disposal of child's feces, covering of water storage container, types of drinking water storage containers, marital status, family size, occupation of mothers, breastfeeding status of the child, duration of water storage, and the presence of feces in the compound.

The bivariate analysis showed that 16 variables, which include maternal education above secondary school level and being self-employed, children aged 6–11 months, poor handwashing practices, improved water sources accessible on premises, water-insecure households, uncovered water storage containers, wide-mouthed water storage containers, sanitation facilities, unsafe child's stool disposal practices, duration of breastfeeding, and handwashing practices at five critical times were significantly associated with diarrheal diseases among under-five children. However, the multivariable logistic regression analysis indicated that only children at 6–11 months of age, HWIS, uncovered water storage containers, wide-mouthed water storage containers, unsafe child's stool disposal practices, hands not washed with soap after defecation, before preparing food, and before feeding a child were significantly associated with the occurrence of diarrheal diseases.

Children at 6–11 months of age were 13 times more likely to develop diarrheal diseases compared with children at 0–5 months of the age group. Children living in water-insecure households were also 4.3 times more likely to develop diarrheal diseases compared with children living in water-secure households. The result also indicated that children whose mothers did not wash their hands with soap after defecation had four times higher odds of developing diarrheal diseases compared with children whose mothers did not wash. Likewise, the odds of developing diarrheal diseases of children whose mothers did not wash their hands with soap before preparing food and before feeding a child were 3.6 and 4.6 times higher than children whose mothers washed their hands with soap before preparing food and before feeding a child, respectively (Table 3).

The study revealed that the prevalence of HWIS (68.6%) was very high in the study area, which is consistent with findings obtained from West Cameroon and Botswana. The findings revealed that the prevalence of water insecurity was 58 and 60% in West Cameron and Botswana, respectively (Kujinga et al. 2014; Nounkeu et al. 2019). The high prevalence of water insecurity in the study area could be associated with the inadequacy of water supply, use of unimproved water sources, and unreliability of the water sources. More than three-fourths (83.3%) of households reported that their main water sources have been interrupted at least once in the last 4 weeks. Furthermore, more than half of the households (53.8%) had to spend more than 30 min collecting water, which might lead to water scarcity and deterioration of water quality. This could further exacerbate water insecurity in the study area. This is in line with findings obtained from the rural South Gonder zone, Ethiopia, which revealed that the use of unprotected water sources and a longer time to fetch water was positively associated with water insecurity (Stevenson et al. 2012). A more recent study conducted in Colombia also indicated that the use of non-piped water sources and water supply interruption was positively associated with water insecurity (Lemaitre et al. 2023). The high prevalence of water insecurity in the study area could affect human health by reducing hygienic practices and increasing the risk of various waterborne diseases.

Overall, the high prevalence of HWIS in the area indicates that households frequently experience insecurity in their water access. When more than half of households spend over 30 min collecting water, it highlights the burden of time and effort required for water procurement. Longer collection time can also impact daily life and well-being (Pickering & Davis 2012). Thus, increased water collection time correlates with higher HWIS (Stevenson et al. 2012). Furthermore, only one-fourth of households had access to improved water accessible on-premise, while three-fourths of households had either unimproved water or improved water sources accessible off-premises, which contributed to the increased prevalence of water insecurity. Storing water for more than 3 days is also commonly practiced by the majority of the study households (73.3%) in the area. While storage provides a buffer against water insecurity, prolonged storage can lead to water quality deterioration (Berihun et al. 2023; Aydamo et al. 2024). This could increase the risk of diarrheal diseases in the study area. The relationship between all these factors suggests the need for a holistic approach, which considers water infrastructure improvement, behavior, and policy to improve household water security, hand hygiene, and reduce waterborne diseases, including diarrhea.

The findings indicated that only 42.2% of the mothers had good handwashing practices (95% CI: 37.5–46.9%). This is consistent with findings obtained from Northwest Ethiopia (39.1%) (Taddese et al. 2020), rural areas of the Gedeo zone (44.9%) (Agaro et al. 2022), and Woldia town in northeastern Ethiopia (46.5%) (Getahun & Adane 2021). The result is lower than other findings obtained from Debark town (52.2%) (Dagne et al. 2019) and Kolladiba town, Northwest Ethiopia (51.2%) (Wolde D et al. 2022; Wolde M et al. 2022). The discrepancies might be associated with the study setting, water insecurity status of the households, low handwashing promotion, socio-economic condition, and behavioral factors of the study area. The study also attempted to identify factors that influence good handwashing practices. The findings revealed that a mother's good handwashing practices were positively significantly associated with good knowledge of handwashing, positive attitudes toward handwashing, household water security, and the presence of HWF in the compound. This is consistent with findings obtained from Northwest Ethiopia, which revealed that good knowledge of handwashing and the availability of HWF was significantly associated with good handwashing practices (Abebe et al. 2023). Various other studies also showed that factors, which include good knowledge of handwashing (Dagne et al. 2019), positive attitudes toward handwashing (Dagne et al. 2019), and the presence of HWF (Wolde D et al. 2022; Wolde M et al. 2022) were positively associated with good handwashing practices. The findings also showed that water-secure mothers were more likely to have good handwashing practices compared with water-insecure mothers. This is in line with findings obtained from West Cameroon (Nounkeu et al. 2019). This is because water-secure mothers were more likely to have the motivation and adequate drinking water to practice good handwashing habits. The study revealed that the average prevalence of handwashing practices at five critical times was very low (35.1%). This might increase the risk of waterborne diseases that could be prevented by effective handwashing practices.

The 2-week period prevalence of diarrhea among under-five children was 16% (95% CI: 12.5–19.5%). This is in line with findings obtained from Northwest Ethiopia (16.7%) (Gedamu et al. 2017), Debre Berhan town (16.4%) (Shine et al. 2020), Bereh District in Ethiopia (17.3%) (Feleke et al. 2022), Serbo town in Southwest Ethiopia (14.9%) (Kasye et al. 2018), and sub-Saharan Africa (16%) (Adedokun & Yaya 2020). The prevalence is also higher than the findings obtained from Southern Ethiopia (13.6%) (Melese et al. 2019), rural India (9.5%) (Saha et al. 2022), semi-urban areas of Northeastern Ethiopia (11%) (Natnael et al. 2021), Wolaita Sodo town (11%) (Alambo 2015), and rural Ethiopia (11.2%) (Ferede 2020). The higher prevalence of diarrhea in this study might be associated with poor sanitation and hygiene practices, high prevalence of water insecurity, study setting, behavioral and socio-economic factors of the area.

The findings indicated that being a child of 6–11 months of age, uncovered water storage containers, wide-mouthed water storage containers, unsafe child's stool disposal practices, HWIS, hands not washed with soap after defecation, before feeding a child, and preparing food were significantly associated with increased diarrheal diseases. Children between the ages of 6–11 months had a significantly higher risk of developing diarrheal diseases compared with children aged 0–5 months. This is in agreement with findings obtained from Jimma Geneti District and the slums of Addis Ababa, which revealed children of 6–11 months of age were significantly associated with the occurrence of diarrheal diseases (Adane et al. 2018; Mosisa et al. 2021). Various other studies also supported this finding (Ferede 2020; Alemayehu et al. 2021). The higher risk of developing diarrheal diseases in children between the ages of 6–11 months could be associated with several factors. When children are between 6 and 11 months old, they usually start to move from only drinking breast milk to eating other foods as well, which could expose them to a wide range of foods and increase the risk of consuming contaminated food or water, leading to the occurrence of diarrhea (Adane et al. 2018). Besides, the immune systems of infants aged 6–11 months are not fully matured, which makes them susceptible to infections from diarrheal diseases (Mosisa et al. 2021).

Being children from water-insecure households was significantly associated with increased diarrheal diseases compared with children from water-secure households. This is because the lack of safe and adequate water can lead to reduced hygienic practices and also force households to use unsafe water sources, which in turn increases the risk of diarrheal diseases. This is in agreement with findings obtained from Bolivia (Rosinger 2018) and West Cameroon (Nounkeu et al. 2019). Unsafe stool disposal practices have also increased the risk of diarrheal diseases among under-five children, which could be due to the presence of feces in the compound that creates a breeding ground for flies. Flies might carry disease-causing microorganisms and contaminate food and water sources, which could increase the risk of diarrheal diseases (Natnael et al. 2021). This is consistent with findings obtained from India (Paul 2020) and Western Ethiopia (Alemayehu et al. 2021). The finding also indicated that wide-mouthed water storage containers were significantly associated with increased diarrheal diseases, which is in line with findings obtained from Northwest Ethiopia (Zelalem et al. 2017). Children who lived in households that did not cover their water storage containers were more likely to develop diarrheal diseases than children who lived in households that covered their water storage containers, which is in line with findings obtained from Debre Berhan town (Mamo & Hailu 2014) and Nekemte town in Western Ethiopia (Birke 2008). This could be because uncovered water storage containers are more easily contaminated by flies carrying diseases causing microbes and other dirty materials, which can increase the transmission of diarrheal diseases (Birke 2008).

There was a significant association between hands not washed with soap after defecation, before feeding a child and preparing food, and the occurrence of childhood diarrhea. This indicates that of those five critical times, only handwashing with soap after defecation, before preparing food, and before feeding a child can prevent the occurrence of diarrhea. This is in agreement with findings obtained from the slums of Addis Ababa, which revealed that washing hands with soap after defecation and before preparing food were the key practices in preventing diarrhea (Adane et al. 2018). A study conducted in rural Bangladesh also found that washing hands before preparing food was an important practice in preventing the occurrence of diarrhea (Luby et al. 2011).

The study was conducted at one point in time, which makes it difficult to establish the cause–effect relationship. This cross-sectional nature of the study was considered as one limitation. Another limitation is that data on handwashing practices, knowledge, and attitudes toward handwashing were self-reported, which could be associated with social desirability bias. The study did not include the malnutrition status of the children in the analysis, which is another limitation of the study.

The study revealed that the prevalence of diarrhea and HWIS was very high in the study area. HWIS was statistically significantly associated with increased diarrheal diseases among under-five children. The majority of the mothers had poor handwashing practices, and the average prevalence of handwashing practices at five critical times was also very low. Such poor practices of handwashing had contributed to the increased occurrence of diarrheal diseases in the study area. The study also identified that handwashing with soap before feeding a child, after defecation, and before preparing food were key practices in preventing the occurrence of diarrhea. Hence, the findings suggest interventions that aim to reduce water collection time by providing households with access to closer water sources, including private taps, which could help to improve household water security. Local authorities play a vital role in ensuring regular access to drinking water and soap for people living in the peri-urban and informal settlements, which could improve hand hygiene practices and reduce the risk of diarrheal diseases. Key actions local authorities should take include improving water infrastructure, making water affordable through subsidies, and promoting soap usage through public awareness campaigns and accessible distribution. Educating mothers about proper stool disposal practices, appropriate handling of water storage containers, and enhancing sanitation infrastructure further contribute to disease prevention.

We thank the Hosanna town administration office, kebele officials, data collectors, and study participants for their cooperation and commitment during the study time. We would also like to express our gratitude to the Ethiopian Institute of Water Resources (EiWR), Addis Ababa University, and Wachemo University for providing financial support for this research.

The authors received no specific funding for this research.

All authors contributed equally to the methodology, data curation, data analysis, and write-up of the manuscript. Finally, all authors read and approved the final manuscript.

Ethical approval for the study was obtained from the National Research Ethics Review Committee, Ministry of Education, Ethiopia (Ref. No. 7/2-150/M259/35). We acquired a study permit from the Hosanna town administration office and selected kebeles, and we obtained written consent from all households participating in the study.

All relevant data are included in the paper or its Supplementary Information.

The authors declare there is no conflict.