Intestinal helminthic infections among elementary students of Babile town, eastern Ethiopia

Introduction Intestinal helminthic infections are important public health problems in developing countries. In Ethiopia, intestinal parasitic infections are highly prevalent because of low living standards and poor environmental sanitation. There are several areas in Ethiopia from which epidemiological information is lacking including Babile town. The aim of this study was to determine the prevalence of intestinal helminthic infection among students of Babile town. Methods A cross sectional study was conducted from May 14 to June 08, 2012. Stool samples collected from 644 students were examined by the McMaster method. Data were analyzed using SPSS version 16.0. Univariate analysis was carried out using the Chi-square test to check for presence or absence of association between exposure and the presence of infection and odds ratios with 95% CI were computed to measure the strength of association. Logistic regression was used to calculate predictors of helminthic infection. Statistical significance was set at P < 0.05. Results The prevalence of intestinal helminths was 13.8%, of which three students were infected with soil transmitted helminths with a prevalence rate of 0.47%. The prevalence of Hymenolepis nana, Enterobius vermicularis, hookworm, and Trichiura trichiura infections were 13, 0.6, 0.3, and 0.2% respectively. Intestinal helminthic infection was significantly associated with grade and sex of the school children. Conclusion The prevalence of intestinal helminths was low. Health information dissemination is recommended. Since infection by Hymenolepis nana is a long term health problem in the area, provision of regular treatment by anthelminthic drug of choice for hymenolepiasis is also recommended


Introduction
Intestinal helminthic infections are important public health problems in developing countries [1]. They are the most common infections among school age children and they tend to occur in high intensity in this age group [2]. The World Health Organization estimates that over 270 million pre-school children and over 600 million of school children are living in areas where the parasites are intensively transmitted and are in need of treatment and preventive interventions [3].These infections are most prevalent in tropical and subtropical regions of the developing world where adequate water and sanitation facilities are lacking [4].
The global prevalence and number of cases of intestinal helminths infection in school age children have been estimated to be Roundworm 35% (320 millions); Whipworm 25% (233 millions); Hookworm 26% (239 millions), others 14% (128millions) [5]. Other species of intestinal helminths are not widely prevalent. Intestinal helminths rarely cause death. Instead, the burden of disease is related to less mortality than to the chronic and insidious effects on health and nutritional status of the host [6,7]. In addition to their health effects, intestinal helminth infections also impair physical and mental growth of children, thwart educational achievement, and hinder economic development [8,9]. The high prevalence of these infections is closely correlated with poverty, poor environmental hygiene and impoverished health services [10]. Intestinal helminth infections occur in all regions of Africa; particularly in sub-Saharan Africa, they are common and of major health concerns because of factors that predispose man to the infections such as poverty, poor sanitation, ignorance and malnutrition prevail [11].
In Ethiopia, intestinal parasitic infections are highly prevalent because of low living standards, poor environmental sanitation, unsafe human waste disposal systems, inadequacy and lack of safe water supply, and low socio-economic status [12]. Report from a literature survey indicated that Ethiopia has one of the lowest quality drinking water supply and latrine coverage in the world [13].
This could be one reason for why intestinal parasitism has been widespread in Ethiopia. Moreover, parasitic helminthic infections are the second most predominant causes of outpatient morbidity in the country [12].
In Ethiopia the prevalence of Ascaris lumbricoides infection was 29% in the highlands, 35% in the temperate areas and 38% in the lowlands. The prevalence of hookworm infection was highest in the lowlands (24%) followed by the temperate (15%) and highland (7%); whereasTrichuris trichiura infection exhibited similar prevalence's in all altitudinal regions (13% on the average) [14].
So far several studies identifying the prevalence of intestinal parasites in general and the prevalence of intestinal helminths in particular have been carried out in Ethiopia [15][16][17][18][19] In spite of the fact that a number of studies have been undertaken over the years on the prevalence of intestinal helminths among school children in different part of Ethiopia, yet there are several areas in all the regional states from which epidemiological information is lacking including our study area, Babile town. Therefore, this study is aimed at determining the prevalence of intestinal helminthic infections among elementary students of Babile town. It is believed that this study will provide recent information for those who are working in the prevention and control of intestinal helminthiasis.

Methods
This study was conducted in Babile town, Eastern Hararghe from hence received an interview after providing the stool sample. This makes the response rate to be 100%.
All the necessary information was collected using pre-structured questionnaire. Two Technicians from the local health center were recruited and assigned as data collectors. School teachers and unit leaders helped the data collectors in the entire data collection process.
All the time before beginning stool sample collection, the latrines were inspected for cleanliness by the data collectors to get them cleaned. After giving adequate instruction on how to collect the stool sample, each study subject was provided a stool cup and applicator stick to bring at least 3gm of fresh stool sample of his/her own, that was sufficient for egg count by the McMaster method to determine the prevalence and infection intensity of soil transmitted helminths and the prevalence of other helminthic parasites. Unit leaders of the two schools attended students who are small enough for proper stool sample collection. A laboratory Technologist supervised the appropriateness of the stool sample delivered by the study participants before accepting as a sample. After providing the required stool sample, all the students were interviewed by the data collectors for the completion of data collection. Finally each sample was labeled and transported (after being preserved using formalin) to Harar Campus side lab together with filled questionnaire for processing and examination. The generated data were entered, cleaned and analyzed using SPSS

Prevalence of intestinal helminths
The prevalence of intestinal helminths was 13.8% (89 out of 644).
The most prevalent detected parasite was Hymenolepis nana 13% Similarly Trichuris trichiura infected student was with light infection intensity (300 eggs per gram of feces).   [19], and 6.8% in Delgi, Gondar [15]. This difference may be explained by variations in socio-economic status, climatic and geographic condition of the study area as well as local endemicity of the study area for this particular parasite. In our study univariate analyses indicated that more female children 48 (17.1%) were infected with intestinal helminths than male children 41(11.3%) and found to be statistically significant (P = 0.033) ( Table 2). This is in agreement with data obtained from a study in Nigeria; reported as female children (56.6%) were more infected than male children (46.4%) and the difference was statistically significant (P=0.0019) [21].

Risk factor analysis for intestinal helminthic infections
However, it is in disagreement with Gondar's study reported that no statistical significant association was observed between males and females (p = 0.301) [17]. Higher helminthic infections were observed among the age range 5 -14 compared to the age range 15 -25 in the present study although the difference was not statistically significant (P = 0.205) ( Table 2).
In the present study, a strong association between intestinal helminths and grades of students was detected (P = 0.018). That is, the lesser the grades of the students the more will be the intestinal parasites seen. This study also revealed that the existence of an overall intestinal helminthic infection difference between first and second cycle students (P = 0.001). This is in accordance with a previous report in Gondar town indicating that Children in grade one to grade three had a higher prevalence of intestinal helminthic infections than those in grades four to eight (p = 0.031) [17].
Of all the predictors of intestinal helminthic infection, sex is significantly associated with intestinal helminthic infection. Because logistic regression analysis showed that females are two times more likely to develop intestinal helminthic infection than males (Table-3).
This could be due to carelessness and unhygienic habits practiced by female children than male children in Babile town.