Schistosomiasis is one of the most widespread parasitic infections in developing countries [
Schistosomiasis is also one of the most common parasitic diseases and is widespread in many parts of Ethiopia, usually at an altitude between 1,200 and 2,000 meters above sea level [
Schistosomiasis affects human host by slow damage of the host organs due to granuloma formation around the eggs in the tissues. This leads to the development of fibrosis and chronic inflammation in the liver and causes severe damage including bleeding, renal failures, and cancer [
The high prevalence of this infection is closely correlated to infested water bodies (pond, stream, river, and dam) contact during crossing with bare foot, swimming, washing of clothes and utensil, playing, fishing, and irrigation activity [
A cross-sectional study was conducted from February 1 to March 30, 2013, at Sanja Town, northwest Ethiopia.
Sanja Town is located 792 km far from the capital city Addis Ababa on the roadside to Gondar-Humera. Sanja has an altitude of 1800 m above sea level with annual rainfall ranging from 800 to 1800 mm and annual temperature ranging from 25°C to 42°C. There are two elementary schools, one junior and one high school. One health center gives service for the dwellers of the town and the surrounding areas. There is a river known as Sanja that flows throughout the year. Sanja General Elementary School is located on the west of the main road. A total of 2079 (872 male, 1207 female) students were enrolled in the school for 2012/13 academic year.
The study populations were Sanja General Elementary School children who were enrolled in the school during the study period.
The sample size was determined using statistical formula
Sociodemography and possible determinant factors were assessed with pretested and standardized questionnaire, which was translated into the local language, Amharic.
The school children were provided with small, clean, dried, and leak proof container and clean wooden applicator stick. Then, they were informed to bring sizable stool sample of their own. Then, the stool sample was processed and diagnosed microscopically using formol-ether concentration and Kato-Katz techniques. Double Kato-Katz was employed to a template delivering 41.7 mg of stool [
All the necessary reagents, chemicals, and the performance of kits were checked by known positive and negative samples before processing and examination of samples of the study subjects. The data was checked for completeness and any incomplete or misfiled questionnaires were recorrected under supervision. The slides were examined by two microscopists independently under the middle (40x) objective of the microscope. Negative samples were reexamined on the same day at the same time by another laboratory technologist. The result of laboratory examination was recorded on well-prepared format carefully. Ten percent of the total slide was randomly selected and reexamined at the end by experienced laboratory technologist at the University of Gondar, who was blinded for the first examination results.
Data were entered and analyzed using SPSS 20.0 (SPSS Inc., Chicago, 2011) software. Descriptive statistics was used to give a clear picture of background variables. The frequency distribution of both dependent and independent variables was worked out. Multivariate logistic regression was done for assessing associated risk factors and proportions for categorical variables were compared using chi-square test.
Ethical clearance was obtained from research and ethics review committee of School of Biomedical and Laboratory Sciences, University of Gondar. Before starting of the actual data collection, permission was obtained from school director. Additionally, after explaining the importance of the study, an informed written consent was obtained from study participant’s parent/guardian. An assent was also taken from the school children. Those children who were positive for
A total of 385 school children were included in the study. Their mean age was 12.7 years (range: 6 to 15 years) with standard deviation of 2.3. Among these, 132 (34.3%) were males and 253 (65.7%) were females. Most of the school children 312/385 (81%) were between 11 and 15 years. Of the 385 school children, 288 (74.8%) were from Sanja Town while 97 (25.2%) were from the surrounding rural areas (Table
Sociodemographic characteristics of school children in Sanja General Elementary School, Sanja, northwest Ethiopia, 2013.
Sociodemographic characteristics | Number | Percent |
---|---|---|
Sex | ||
Male | 132 | 34.3 |
Female | 253 | 65.7 |
Age (years) | ||
6–10 | 73 | 19 |
11–15 | 312 | 81 |
Residence | ||
Rural | 97 | 25.2 |
Urban | 288 | 74.8 |
Mothers/guardian educational status | ||
Illiterate | 144 | 37.4 |
Read and write | 153 | 39.7 |
Primary school | 62 | 16.1 |
Secondary school and above | 26 | 6.8 |
Respondent grade | ||
One | 46 | 11.9 |
Two | 30 | 7.8 |
Three | 27 | 7.0 |
Four | 25 | 6.5 |
Five | 47 | 12.2 |
Six | 69 | 17.9 |
Seven | 64 | 16.6 |
Eight | 77 | 20.0 |
|
||
Total | 385 | 100 |
Among the total 385 school children examined, 372 (96.6%) were positive for
Prevalence of
Parasite | Male | Female | Total |
|
|
---|---|---|---|---|---|
|
|
|
|||
|
119 (34.4)** | 227 (65.6) | 346 (89.9) | 0.895 | 0.02 |
Hookworm | 49 (34.3) | 94 (65.7) | 143 (37.1) | 0.995 | 0.00 |
|
24 (38.7) | 38 (61.3) | 62 (16.1) | 0.423 | 0.46 |
|
3 (100) | 0 (0) | 3 (0.8) | 0.016* | 5.80 |
|
0 (0) | 6 (100) | 6 (1.6) | 0.075 | 3.18 |
|
3 (41.9) | 18 (58.1) | 31 (8.1) | 0.47 | 3.94 |
|
|||||
Total | 124 (33.3) | 248 (66.7) | 372 (96.6) | 0.035* | 4.44 |
**Figures in parenthesis indicate percentages.
Regarding parasitic load, the highest number of egg count per gram of faeces (EPG) for
The intensity of
Parasite | Intensity | ||
---|---|---|---|
Light | Moderate | Heavy | |
|
71 (18.4)** | 181 (47) | 72 (18.7) |
|
25 (6.5) | 0 (0) | 0 (0) |
Hookworm | 29 (7.5) | 0 (0) | 0 (0) |
|
1 (0.3) | 0 (0) | 0 (0) |
|
|||
Total | 126 (32.7) | 181 (47) | 72 (18.7) |
Of the total 385 school children examined, 119/132 (90.2%) male and 227/253 (89.7%) female school children were positive for schistosomiasis. The distribution of
Multivariate analysis for factors potentially associated with
Risk factors |
|
OR (95% CI) |
|
|||
---|---|---|---|---|---|---|
Positive | Negative | Total | COR | AOR | ||
Sex | ||||||
Male | 119 (90.2) | 13 (9.8) | 132 (34.3) | 0.95 (0.45, 2.02) | 0.86 (0.41, 1.80) | 0.69 |
Female | 227 (89.7) | 26 (10.3) | 253 (65.7) | 100 | 100 | |
Age (years) | ||||||
6–10 | 66 (90.4) | 7 (9.6) | 73 (19.0) | 0.93 (0.36, 2.32) | 0.63 (0.18, 2.20) | 0.47 |
11–15 | 280 (89.7) | 32 (10.3) | 312 (81.0) | 100 | 100 | |
Resident | ||||||
Rural | 86 (88.7) | 11 (11.3) | 97 (25.2) | 100 | 100 | 0.53 |
Urban | 260 (90.3) | 28 (9.7) | 288 (74.8) | 0.84 (0.38, 1.89) | 0.78 (0.37, 1.66) | |
Grade | ||||||
One–four | 118 (92.2) | 10 (7.8) | 128 (33.2) | 0.67 (0.29, 1.49) | 2.02 (0.67, 6.10) | 0.22 |
Five–eight | 228 (88.7) | 29 (11.3) | 257 (66.8) | 100 | 100 | |
Mothers/guardian edu. status | ||||||
Illiterate | 131 (91.0) | 13 (9.0) | 144 (37.4) | 0.50 (0.20, 1.26) | 0.43 (0.13, 1.21) | 0.36 |
Read and write/1ry | 154 (91.7) | 14 (8.3) | 168 (43.6) | 0.46 (0.19, 1.14) | 0.37 (0.11, 1.09) | |
2ry school and above | 61 (83.6) | 12 (16.4) | 73 (19.0) | 100 | 100 | |
Swimming in river | ||||||
Yes | 106 (79.7) | 27 (20.3) | 133 (34.5) | 5.09 (2.37, 11.1) | 5.12 (3.47, 17.89)• | 0.01 |
No | 240 (95.2) | 12 (4.8) | 252 (65.5) | 100 | 100 | |
Swimming frequency/wk | ||||||
0 | 70 (79.5) | 18 (20.5) | 88 (22.9) | 1.00 | 1.00 | 0.00 |
1-2 | 170 (90.9) | 17 (9.1) | 187 (48.6) | 2.57 (1.18, 5.60) | 1.82 (0.79, 4.23) | |
≥3 | 106 (96.4) | 4 (3.6) | 110 (28.5) | 6.81 (2.05, 24.95) | 4.83 (1.37, 18.81)• | |
Washing clothes in river | ||||||
Yes | 101 (79.5) | 26 (20.5) | 127 (33.0) | 4.85 (2.28, 10.43) | 5.54 (2.89, 13.76)• | 0.00 |
No | 245 (95.0) | 13 (5.0) | 258 (67.0) | 100 | 100 | |
Washing utensil in river | ||||||
Yes | 68 (78.2) | 19 (21.8) | 87 (22.6) | 3.88 (1.86, 8.09) | 4.91 (2.43, 12.37)• | 0.00 |
No | 278 (93.3) | 20 (6.7) | 298 (77.4) | 100 | 100 | |
Crossing river with bare foot | ||||||
Yes | 75 (77.3) | 22 (22.7) | 97 (25.2) | 4.62 (2.25, 9.77) | 3.95 (2.13, 7.61)• | 0.00 |
No | 271 (94.1) | 17 (5.9) | 288 (74.8) | 100 | 100 | |
Fishing in the river | ||||||
Yes | 110 (82.1) | 24 (17.9) | 134 (34.8) | 3.20 (1.56, 6.62) | 3.04 (2.14, 8.71)• | 0.00 |
No | 235 (93.6) | 16 (6.4) | 251 (65.2) | 100 | 100 | |
|
||||||
Total | 346 (89.9) | 39 (10.1) | 385 (100) |
Determinant factors assessment for
In multivariate analysis, swimming in the river and frequent swimming habit were associated with
The prevalence rate of 89.9%
The intensity of
The sex distribution of
The prevalence of
The habit of frequent contact with cercariae infested water such as swimming in the river, washing clothes and utensils using river water, crossing the river with bare foot, and fishing activities showed a statistically significant association with prevalence of
Ninety percent of the school children were infected with
The authors declare that there is no conflict of interests regarding the publication of this paper.
Ligabaw Worku conceived the study, undertook statistical analysis, and drafted the initial and final paper. Mulugeta Aemero, Demekech Damte, and Mengistu Endris initiated the study and made major contributions to the study design, reviewed the initial and final drafts of the paper, and conducted data analysis. Habtie Tesfa participated in sample collection and performed laboratory diagnosis. All authors contributed to the writing of the paper and approved the submitted version of the paper.
The authors would like to thank the University of Gondar for the financial support and the Department of Medical Parasitology for providing excellent laboratory facilities for processing the stool samples. They are also thankful to staff members of Sanja Health Center for treating the infected school children and Sanja General Elementary School staff members for supporting field work. Lastly, their thanks go to all the parents/guardians for their consent and the children who participated in this study.