Introduction
Intestinal parasitic infections (IPIs) continue to pose a major public health challenge, especially in populations facing poverty and poor living conditions [1]. These infections thrive in environments with overcrowding, inadequate sanitation, unsafe waste disposal, and limited access to clean water. The absence of proper sewage systems and contamination of water sources further increase transmission risks [2].
Poor hygiene practices, such as infrequent handwashing and improper food handling, also play a key role, particularly where hygiene education and basic resources are lacking [3]. Vulnerable groups, including young children, the elderly, and those with weakened immune systems from conditions like HIV/AIDS, are more susceptible and often experience more severe illness [4].
Globally, over 3.5 billion people are affected by IPIs, with approximately 450 million individuals suffering from related illnesses [5]. The burden is particularly heavy in sub-Saharan Africa, where children are disproportionately impacted [6]. Among the causative agents, soil-transmitted helminths (STHs), including Ascaris lumbricoides, hookworm, and Trichuris trichiura infect more than 1.5 billion people worldwide [7].
Additionally, protozoal infections caused by Giardia lamblia, Entamoeba histolytica, and Cryptosporidium are among the most common in developing countries [8].
The fecal-oral pathway, which involves ingesting contaminated food, water, or soil, or larvae penetrating the skin (L3 stage), is the primary mode of transmission. The cycle of infection is maintained by parasites released in feces. Growth delays, malnourishment, anemia, and poor cognitive development can result from these diseases [9].
To assist control of IPIs, particularly in children, deworming programs are frequently implemented in schools, hospitals, and health facilities. Even though these programs have been beneficial, problems still exist. In regions where many individuals are affected and malnutrition is frequent, multiple treatments and support from diverse facilities are needed to keep the illnesses under control [10].
Studies across various countries have revealed a wide range of prevalence rates for IPIs among children, reflecting significant regional variations [11–14]. In Ethiopia, reported rates of IPIs among children have ranged from 9.02% to 58% [15–19], highlighting the considerable public health challenge posed by these infections. The absence of comprehensive data on IPIs among children under five years of age complicates the development of effective public health strategies and the optimal allocation of healthcare resources.
This study was conducted at Bule Hora University Teaching Hospital (BHUTH), a major healthcare facility serving both urban and rural populations in Southern Ethiopia. The hospital receives a high volume of pediatric patients from diverse socio-demographic backgrounds, particularly from communities with poor sanitation, limited access to clean water, and inadequate healthcare infrastructure, conditions that are strongly associated with a high burden of parasitic infections [20]. The objective of this study was to determine the prevalence of IPIs and identify associated risk factors among children attending BHUTH.
Findings from this context aim to generate clinically relevant data that can guide local health interventions and contribute to broader public health planning in similar low-resource settings.
Method
Study area, design, and study period
A hospital-based cross-sectional study was conducted between June and August 2024 among children under five years of age who visited the pediatric clinic/outpatient department (OPD) of BHUTH in Southern Ethiopia for routine and/or symptomatic medical evaluations. Bule Hora, located 475 km from the capital Addis Ababa, is situated in the West Guji Zone of the Oromia region at a latitude of 5°35′N and longitude 38°15′E, with an elevation of 1,716 m above sea level [21]. The hospital currently serves a catchment population of over 1.3 million people from Bule Hora and surrounding areas, including neighboring provinces in the Southern Nations, Nationalities, and Peoples’ Regional State (SNNPR).
It plays a central role in providing clinical services and training students across various disciplines.
Source population
All children under the age of five who visited the pediatric clinic/OPD of BHUTH for routine and/or symptomatic medical evaluations were the source population.
Study population
All children under the age of five who visited the pediatric clinic/OPD of BHUTH during the study period and met the inclusion criteria were included in the study.
Eligibility criteria
Inclusion criteria
All children under the age of five who visited the pediatric clinic/OPD of BHUTH during the study period were included in the study.
Exclusion criteria
Children who had received antiparasitic treatment within the past 2–4 weeks or were severely ill at the time of the study were excluded.
Sample size determination and sampling techniques
The sample size for this study was determined using the single population proportion formula, with a 95% confidence level (Z = 1.96) and a 5% margin of error. Based on a proportion from a study conducted in Hawassa [22] and factoring in a 5% non-response rate, the final sample size was calculated to be 315.\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:n=\frac{{\left(Z\alpha\:/2\:\right)}^{2}P\left(1-p\right)}{{\left(d\right)}^{2}}$$\end{document}\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:n=\frac{{\left(1.96\right)}^{2}*0.266\:\left(1-0.266\right)}{{\left(0.05\right)}^{2}}=300$$\end{document}\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$n=300$$\end{document}
Thus, accounting for a 5% non-response rate, a total of 315 study participants were included in the research.
Sampling techniques
The monthly estimate of children under five attending BHUTH was derived from the pediatric clinic/OPD records. On average, 30–40 children per day receive services in the pediatric clinic/OPD. A systematic random sampling method was employed to select study participants.
To calculate the sampling interval (k), the total number of children (1,138), estimated number of children per month receiving services in the pediatric clinic/OPD was divided by the required sample size (315), yielding K = N/n = 1,138/315 = 3.61 ≈ 4. Here, N represents the total number of children attending the pediatric clinic/OPD, n is the sample size, and K is the interval. As a result, every fourth child under five years old was selected until the target sample size was reached.
This approach continued throughout the data collection period until the desired sample size was attained.
Data collection and laboratory methods
Data collection
Data on sociodemographic characteristics and factors associated with IPIs were gathered using a pre-tested, semi-structured questionnaire administered through face-to-face interviews. A structured questionnaire was developed in English after reviewing relevant literature [16, 22, 23] and incorporating expert feedback. The questionnaire consisted of three main sections: (1) socio-demographic characteristics of the child and caregiver (2), environmental and behavioral conditions, and (3) child health and hygiene practices.
The tool was translated into Afan Oromo, the local language, to ensure participant comprehension. A back-translation into English was performed by an independent bilingual expert to ensure semantic equivalence. Discrepancies were reviewed and resolved through consensus among the research team.
Laboratory methods
Stool specimen collection, processing, and examination
Before specimen collection, the caretakers of the participating children were provided with an overview of the procedure. Plastic stool containers with applicator sticks, each labeled with identification numbers, were given to the caretakers of the selected children. Mothers/guardians were instructed to provide approximately 2–5 g of fresh stool.
For children below 1 year, a special technique was used by placing plastic wrap or a non-absorbent liner inside the diaper to prevent urine contamination and allow clean sample retrieval, whereas for older children, the stool was collected directly by their guardians using the provided stool cup. For each sample, a direct saline wet mount was initially prepared by mixing a small portion of the stool with a drop of physiological saline using an applicator stick. The preparation was then covered with a coverslip and examined microscopically under both low-power (10×) and high-power (40×) objectives to identify motile trophozoites and other parasitic forms, following the method described by Cheesbrough [24].
The remaining portion of the stool sample was then used for the formol-ether concentration technique. Approximately 1 gram of stool was emulsified in 7 mL of 10% formalin water in a screw-capped tube and thoroughly mixed. The resulting suspension was filtered through a gauze-lined funnel into a second clean centrifuge tube to remove large debris.
Next, 3–4 mL of ethyl acetate was added to the filtrate. The tube was securely capped and shaken vigorously for about 30 s to 1 min to ensure thorough mixing. The mixture was then centrifuged at a minimum speed of 2,500 revolutions per minute (rpm) for 5 min.
Following centrifugation, the resulting four layers were observed: a top layer of ethyl acetate, a plug of debris, a formalin layer, and a sediment at the bottom. The top three layers were carefully discarded without disturbing the sediment. The sediment was then examined microscopically under both 10× and 40× objectives to detect cysts, eggs, and larvae of intestinal parasites [25].
Quality assurance
To ensure the reliability of both questionnaire and laboratory data, multiple quality control measures were implemented. The questionnaire was pre-tested on 5% of the target population at Kerach Primary Hospital, and necessary modifications were made based on participant feedback. For laboratory procedures, standard operating protocols (SOPs) for stool sample collection and microscopic examination were strictly followed.
The quality of normal saline used in the laboratory was verified to maintain internal quality control and minimize technical errors. Each stool sample was independently examined by two trained laboratory technicians at separate times using the same slide, and their findings were compared to ensure consistency and accuracy. Any discrepancies were resolved through discussion and, when necessary, consultation with senior laboratory professionals.
Additionally, the principal investigators reviewed the completed data collection tools daily to verify completeness and accuracy.
Data analysis and interpretations
The collected data was coded and entered into EPI-Data version 4.6, then exported to SPSS version 25 for analysis. Socio-demographic characteristics and other relevant variables were summarized using descriptive statistics, including frequencies and percentages, to provide a clear overview of the study population. Variables with a P-value < 0.25 in the bivariable analysis were further examined using multivariable logistic regression to identify independently associated factors.
A variable with a P-value < 0.05 and a 95% confidence interval in the multivariable logistic regression was considered statistically significant.
Ethics consideration
The study protocol received ethical clearance from the Institutional Health Research Ethics Review Committee of the Institute of Health, Bule Hora University (Ref. No: BHU/IOH/IRERC/016/19; dated July 18, 2024). A formal letter of support was also granted by BHUTH.
All study procedures were conducted in full compliance with recognized ethical standards, including the principles outlined in the Declaration of Helsinki. Before participation, written informed consent was obtained from the parents or legal guardians of the children after providing them with comprehensive information regarding the study’s objectives, methodology, potential risks, and anticipated benefits. Participants were assured of their right to voluntarily withdraw from the study at any point, without any repercussions.
Results
Socio-demographic characteristics of the study participants
A total of 315 participants were included in this study, consisting of 180 females (57.1%) and 135 males (42.9%). The largest age group of participants was between 24 and 59 months, comprising 94 children (29.8%). Approximately 170 participants (54%) resided in urban areas.
In terms of maternal education, 154 mothers (48.9%) were literate, and many mothers were housewives, with 109 (34.6%) falling into this category (Table 1).
Table 1Socio-demographic characteristics of children under five years attending Bule Hora University Teaching Hospital (BHUTH), Southern Ethiopia (N = 315)VariablesCategoryNumber (%)GenderMale135 (42.9)Female180 (57.1)Age (months)< 653 (16.8)6–1190 (28.6)12–2378 (24.8)24–5994 (29.8)ResidenceUrban145 (46)Rural170 (54)Mothers’/guardians’ educational statusIlliterate76 (24.1)Read and write154 (48.9)Elementary43 (13.7)High school and above42 (13.3)Mother occupationHousewife109 (34.6)Employed62 (19.4)Farmer93 (29.5)Merchant52 (16.5)
Frequency distribution of behavioral and environmental factors among the study participants
Among the study participants, 205 (65%) obtained their drinking water from tap sources, while 110 (35%) relied on groundwater. Access to toilet facilities at home was reported by 195 mothers/guardians of the children (61.9%). Although 172 (54.6%) mothers or guardians had awareness of the transmission modes of IPs, 143 (45.4%) lacked such knowledge.
In terms of hygiene practices, only 155 (49.2%) of mothers or guardians consistently washed their hands after defecation, while a slightly higher number, 160 (50.8%), reported doing so only occasionally. A total of 75 (28.62%) admitted to having a habit of eating unwashed fruits, whereas the majority, 187 (71.37%), stated that they do not give unwashed fruits to their children. Concerning children’s hygiene, 167 (53%) of mothers or guardians indicated that their children habitually trim their nails, and 166 (52.7%) reported that their children habitually wash their hands before meals (Table 2).
Table 2Frequency distribution of behavioral and environmental risk factors among children under five years attending Bule Hora University Teaching Hospital (BHUTH), Southern EthiopiaVariablesCategoryNumber (%)Source of drinking waterTap205 (65)Ground water110 (35)Latrines are available at homeYes195 (61.9)No120 (38)Hand washing habit of the mother/guardian followingdefectionAlways155 (49.2)Sometimes160 (50.8)Does your child eat unwashed fruit?Yes75 (28.62)No187 (71.37)Mother/ guardian awareness about the mode of transmissionYes172 (54.6)No143 (45.4)Are your child’s nails trimmed?Yes148 (47)No167 (53)Your child’s recreational areaClean139 (44.1)Not clean176 (55.8)Does your child regularly wash their hands before meals?Yes166 (52.7)No149 (47.3)
Prevalence and frequency distribution of identified intestinal parasite (IP) species among the study participants
In this study, the overall prevalence of IPs among children under five years of age was 29.8% (94/315). Giardia lamblia was the most frequently identified parasite, present in 39 cases (41.5%), of which 24 (61.5%) were diagnosed with cysts and 15 (38.5%) with trophozoites. This was followed by Entamoeba histolytica, detected in 25 cases (26.6%), with 16 (64%) diagnosed with cysts and 9 (36%) with trophozoites, A. lumbricoides in 18 (19.1%), H. nana in 8 (8.5%), and T. trichiura in 4 (4.2%) cases.
While single infections were prevalent, a co-infection of G. lamblia and E. histolytica was found in six (1.9%) children; however, no triple infections were recorded in this study (Fig. 1).
Fig. 1Frequency distribution of identified IP species among infected under-five children attending Bule Hora University Teaching Hospital (BHUTH), Southern Ethiopia
Factors influencing the prevalence of intestinal parasitic infections (IPIs) among the study participants
This study examines the factors contributing to the prevalence of IPIs among children under five. Female children under five were more commonly affected by IPs than males. Additionally, the age group of 24–59 months exhibited the highest prevalence of IPIs.
Among the participants, tap water users (66/205*100 = 32.2%) demonstrated higher rates of IPIs compared to groundwater users. Additionally, mothers who habitually wash their hands after defecation (40/155*100 = 25.8%) exhibited fewer IPIs than those without this habit (54/160*100 = 33.8%). Participants who habitually eat unwashed vegetables, children with unclean recreational areas, children who do not wash their hands before meals, and mothers/guardians lacking awareness of transmission methods exhibit the highest prevalence of IPIs.
Variables significant in bivariable analysis underwent multivariable logistic regression analysis. The multivariable analysis revealed that certain factors, including the habit of consuming unwashed fruits and vegetables, mothers or guardians’ lack of awareness regarding the transmission mode of parasitic infections, and children residing in rural areas, were significantly associated with IPIs, with a p-value of less than 0.05.
The study found that mothers or guardians who were unaware of the transmission routes for parasitic infections had a significantly higher likelihood of their children being affected by IPs (AOR = 3.358, 95% CI = 1.734–7.99). Additionally, the study highlighted those children living in rural areas had a higher prevalence of IPIs compared to their urban counterparts. Specifically, children from rural areas were found to be twice as likely to be infected with IPs compared to those living in urban settings (AOR = 2.011, 95% CI = 1.127–3.589) (Table 3).
Table 3Bivariable and multivariable logistic regression analysis for factors associated with IPIs among under-five children attending Bule Hora University Teaching Hospital (BHUTH), Southern EthiopiaVariablesCategoryIPIsCOR (95% CI)AOR (95% CI)P-valuePositive; N (%)Negative; N (%)GenderMale39 (28.8)96 (71.1)11Female55 (30.5)125 (69.5)0.923 (0.566–1.506)0.806 (0.433–1.48)0.487Age (months)< 62 (3.8)51 (96.3)116–1133 (36.7)57 (63.3)0.35 (0.05–0.2640.902 (0.121-2)0.87912–2320 (25.6)58 (82)0.52 (0.28–0.964)1.624 (0.43–6.13)0.47524–5939 (41.5)55 (58.5)0.02 (0.261–0.894)0.95 (0.533–1.69)0.863ResidenceUrban31 (21.4)114 (78.6)110.018*Rural63 (37)107 (63)2.165 (1.307–3.586)2.011 (1.127–3.589)Educational status of mother/guardianIlliterate16 (38)26 (62)0.4 (0.172–0.926)0.56 (0.23–0.9.46)0.3839Read and write47 (30.5)107 (69.5)0.714 (0.351–1.453)0.65 (0.52–1.367)0.236Elementary16 (37.2)27 (62.8)0.963 (0.4-2.316)0.85 (0.34–1.788)0.789High school and above15 (19.7)61 (80.3)111Source of drinking waterTap66 (27)178 (73)11-Ground water28 (39.4)43 (60.5)1.756 (1.010–3.054)1.31 (1.02–4.65)0.893Presence of a latrine at homeYes33 (27.5)87 (72.5)0.833 (0.504–1.377)0.565 (0.367–1.67)0.457No61 (31.3)134 (68.7)11-Hand washing habit of the mother/guardian following defectionYes40 (25.8)115 (74.2)11-No54 (33.8)106 (66.2)1.465 (0.900-2.383)1.25 (0.680–1.956)0.668Habit of eating unwashed fruit and vegetablesYes59 (45)72 (55)3.488 (2.107–5775)3.11 (1.301–7.448)0.011*No35 (19)149 (81)11Mother/ guardian awareness about the mode of transmissionYes28 (16.5)144 (84)110.012*No66 (46.5)77 (54)4.408 (2.617–7.426)3.358 (1.734–7499)Notes: AOR = Adjusted odd, CI = Confidence interval, COR = Crude odd ratio, IPI = Intestinal parasitic infections
Discussion
Intestinal parasitic infections (IPIs) persist as a relevant public health concern in several regions, particularly in developing countries like Ethiopia [1]. In these regions, many people lack access to clean drinking water and live in poverty. Our study identified a prevalence of IPIs of 29.8% (95% CI = 22.5–34.8%), which aligns with findings from other regional studies.
For instance, a study conducted at Adare Hospital in Hawassa reported a comparable prevalence of 26.6%, suggesting a consistent burden of IPIs across comparable settings in the region [22], in the West Omo zone (29.4%) [17], in Bahir Dar city (24.4%) [26], and in Northern Mozambique (31.6%) [27]. These findings suggest widespread vulnerability, particularly among young children. Addressing IPIs is crucial for improving child health outcomes and reducing morbidity in affected populations [9, 28].
Our study found that children under the age of five are especially at risk for helminth infections, mainly because sources of infection are still present in their surroundings. Other studies have shown that deworming programs can help reduce the number of infections caused by soil-transmitted helminths like Trichuris trichiura, Ascaris lumbricoides, and hookworms in young children. These programs have been effective in lowering transmission and improving children’s health [29–31].
However, our study observed a higher prevalence compared to studies conducted at Dessie referral hospital (15.5%) [32], Debre Birhan referral hospital (17.4%) [28], and a study conducted in Kenya (17.3%) [33]. Variations in hygiene and sanitation practices, socioeconomic status, cultural behaviors, and nutritional health significantly influence infection rates and may account for differences observed between studies. For example, regions with limited access to clean water and poor sanitation tend to have a higher prevalence of helminth infections.
Additionally, subtle differences in sampling techniques and diagnostic methods can also contribute to inconsistent results. Considering these factors together provides a more thorough explanation for the varying outcomes reported in studies with similar methodologies [34, 35].
The widespread prevalence of Giardia lamblia can be largely attributed to poor sanitation and inadequate water quality control [32, 36, 37]. Children are particularly vulnerable to exposure to fecal matter, especially during nappy changes, toilet training, or at daycare facilities, which increases their risk of infection. Additionally, Giardia thrives in environments with poor sanitation, where water and food may become contaminated [38].
In this study, G. lamblia emerged as the most frequently identified parasite, detected in 39 cases (41.5%), with cysts observed in 24 (61.5%) and trophozoites in 15 (38.5%) cases. This was followed by E. histolytica, identified in 25 children (26.6%), of whom 16 (64%) harbored cysts and 9 (36%) trophozoites. Although single infections were more common, co-infections involving both G. lamblia and E. histolytica were documented in six children (1.9%), underscoring the possibility of overlapping exposures and shared transmission routes.
This finding is consistent with studies conducted at Bahir Dar and Dessie Referral Hospitals in Ethiopia [32, 39].
In this study, factors associated with IPIs included lack of awareness about transmission among mothers or guardians (AOR = 3.358, 95% CI = 1.734–7.99), residence in rural areas (AOR = 2.011, 95% CI = 1.127–3.589), and regular consumption of unwashed vegetables by children (AOR = 3.11, 95% CI = 1.301–7.448) [1, 40]. Children whose mothers or guardians were unaware of parasitic transmission were 3.36 times more likely to be infected with IPIs (AOR = 3.358, 95% CI = 1.734–7.99). This highlights the impact of caregiver knowledge on child health, as a lack of awareness can contribute to poor hygiene and sanitation practices.
The finding is consistent with a study from Bahir Dar, Ethiopia, which also reported a strong link between parental knowledge and IPI risk [39].
A lack of knowledge about parasite transmission can lead to poor adherence to preventive practices, such as proper handwashing, food preparation, and sanitation [41]. Additionally, the study found that children living in rural areas are twice as likely to suffer from IPIs compared to their urban counterparts (AOR = 2.011, 95% CI = 1.127–3.5867). This finding is consistent with prior studies conducted in the West Omo zone [1, 9, 17].
The heightened vulnerability in rural areas may be attributed to common childhood behaviors, such as nail-biting, not washing hands before meals, and improper toilet use. These behaviors, coupled with low socioeconomic status and limited access to deworming services, contribute to increased transmission and incidence of infections [17, 42, 43].
Strengths and limitations of the study
A key strength of this study is its focus on a vulnerable pediatric population in a clinical setting, providing timely, context-specific data on the prevalence and risk factors of IPIs, which can inform local health planning and targeted interventions. However, as a hospital-based cross-sectional study, it may be subject to selection bias and may not fully reflect the prevalence in the general population. Stool microscopy, while standard, has limited sensitivity for detecting low-intensity infections.
Additionally, the proportion of children presenting with diarrhea was not systematically recorded, and the intensity of STH infections was not assessed, limiting the clinical interpretation of the findings. A sensitivity analysis was not performed, as the study aimed to identify associations using well-defined variables and minimal missing data; nonetheless, incorporating one could strengthen future studies.
Conclusion
This study found an overall prevalence of IPIs of 29.8%, a significant figure that calls for focused efforts to reduce and control these infections. The most common parasite was Giardia lamblia (39 cases, 41.5%), followed by Entamoeba histolytica/Entamoeba dispar (25 cases, 26.6%), and Ascaris lumbricoides (18 cases, 19.1%). The study also identified key factors significantly associated with the prevalence of IPIs in children: residing in rural areas, consistently eating unwashed vegetables, and having mothers or guardians who lacked awareness of the transmission modes of parasitic infections.
Recommendation
To mitigate the spread of IPIs, it is crucial to strengthen health education, enhance awareness among mothers and guardians about the transmission of IPs, and promote better hygiene practices for children. Health education initiatives and improved access to healthcare facilities play key roles in controlling infections. We also recommend promotion of mass deworming efforts to prevent and control infections in children.
Additionally, large-scale studies should be conducted to gain a deeper understanding of infection patterns and trends across different populations in the study area.