Epidemiological studies on the prevalence with infection of intestinal parasites in different localities have as a primary objective to identify high-risk communities and formulate appropriate interventions. In line with this view, the present study attempted to assess the prevalence of different intestinal parasitic infections in schoolchildren in a private community school in Gondar town, Northwest Ethiopia, The results of the study showed the occurrence of several intestinal parasites of public health importance among schoolchildren.
The observed prevalence of intestinal parasites of 104 (34.2%) was lower compared with reports of other similar studies, 72.9% in Gondar, Azezo [10], 83% in Jimma [11] and 83.8% in South East of Lake Langano [13]. On the other hand, the prevalence observed in this study was higher than a study conducted in Babile (27.2%) [14]. These variations in prevalence might be due to differences in climatic conditions, environmental sanitation, economic and educational status of parents and study subjects, and previous control efforts.
According to the present study, the prevalence of Hymenolepis nana, Entamoeba histolytica/dispar, and Ascaris lumbricoides were 13.8%, 9.2%, and 5.9%, respectively. Infections with Entamoeba histolytica/dispar was more prevalent among the female population, while Hymenolepis nana affected more males but the association was not statistically significant (p > 0.05). These three parasites are prevalent among lower age groups. This finding is in line with a study conducted in Metema District Hospital [15]. On the other hand, the prevalence of Ascaris lumbricoides, hookworm and Schistosoma mansoni were lower compared to a school-based study done in Azezo, Gondar [10]. This difference might be due to improved environmental sanitation in the community school as compared to Azezo elementary school, regular wearing of shoes and better family income among the study participants.
In this study, multiple infections (polyparasitism) occurred in 14 individuals or 4.6% of the total examined subjects and 13.5% of those who had intestinal parasites. This prevalence is lower compared with similar studies in Gondar, Azezo [10]. Double infections were seen in six study subjects with intestinal parasites. The prevalence of multiple infections was very low compared to previous studies [13, 16]. Sample size, study population and the methods used could attribute to this observed difference in detections of various parasites.
In this study, 36.2% of the study participants practice good hand washing before eating and after toilet using soap and water. Intestinal parasitic infections were significantly associated with poor hand washing practice (p < 0.05). The likelihood of acquiring infections among students who do not practice hand washing was 6.45 (95% CI = 4.55- 11.90) times higher than among those who had good hand washing practice. Similarly, ways of transportation to the school had statistically significant association with parasitic infections. This finding is consistent with a study conducted in Babile town [14]. Similar to a report in Zarima town [17], the level of education of the study participants was significantly associated with intestinal parasitic infections. However, family monthly income, number of siblings, religion and swimming habit did not show statistically significant associations with intestinal parasitic infections (P > 0.05) (Table 4).
In this study, protozoan infections were more prevalent in schoolchildren especially in those under 12 years of age while there was reduction as age increased. The reason could be due to the slow development of immunity in adults to protozoan parasites and better awareness in washing hands and other personal hygiene measures. On the other hand, there was no significant difference in the rate of infection due to helminths in relation to the age of students. This might be due to different evasion mechanisms to immunity by helminths.
The present study was subjected to the following limitations. The study was non-blinded. Due to lack of antigen tests, Entamoeba histolytica and Entamoeba dispar were not separated. As the collection period was short, potential seasonal fluctuations might have affected the actual prevalence. Modified acid-fast staining technique was not used to detect Cryptosporidium species.