Molecular diagnosis of urogenital schistosomiasis in pre-school children, school-aged children and women of reproductive age at community level in central Senegal

Abstract

Background: Urogenital schistosomiasis is a major public health concerns in Sub-Saharan Africa. In Senegal, the disease is endemic in all the regions of the country. Recently, WHO strongly recommend including the pre-school children and the women of reproductive age during the mass drug administration campaign. So, it is important to describe the burden of the disease in these group at risk using innovative diagnosis tools. This study aimed to assess the use of real time PCR in the detection of schistosomiasis cases at community level in a seasonal transmission area. Materials and methods: A cross sectional survey was carried out in Niakhar located in the centre of Senegal. Pre-schoolchildren, school-aged children and female adolescents and adults were invited to participate in the study in April 2018. Urine samples were collected and examined using hemastix reagents strips, filtration technique and real-time PCR. Schistosoma haematobium was detected identified by targeting the Dra1 gene. The prevalence of urogenital schistosomiasis was determined for each group and the performance of the real-time PCR was compared with the conventional techniques. Results: A total of 428 participants were enrolled in this study including 87 (20.3%) pre-school children (1-5 years), 262 (61.2%) school-aged children between (5-14 years), 17 (3.9%) adolescents (15-17 years) and 62 (14.4%) female adults. The comparison of the diagnostic techniques has shown that the prevalence of urogenital schistosomiasis is more important using molecular technique (34.6%) compared to the microscopy (20.3%). The percentage rate of hematuria using the hemastix was 23.1%. School-aged children between 5 and 14 years old were the most affected with 29.0% and 43.1% under microscopy and RT-PCR respectively. In female participants, the microscopic prevalence decreases with the age, from 21.4% in school-aged children to 17.6% in adolescents and 9.7% in adults. There was a good correlation between the number of eggs per 10 ml and the cycle threshold range. Conclusion: These results show the importance of the use of molecular tools in the surveillance of schistosomiasis particularly in pre-school children and women of reproductive age.