O0242 Oct.5: 10:21am - The Epidemiology of a Hidden Schistosomiasis Endemic in the Salamat Region of Chad, Africa

Background: The Republic of Chad in north-central Africa is ranked in the bottom three of the World Health Organization (WHO) Multidimensional Poverty Index. Though it is a schistosomiasis-endemic country with an estimated two million school-aged children affected, there is currently a severe paucity of local epidemiologic data for this disease, particularly in rural communities dependent on surface water. Because schistosomiasis is known to have large regional variations in prevalence, this knowledge gap hinders attempts at a national control strategy.

Objective: Our study seeks to address the knowledge gap by describing the epidemiology and treatment of endemic schistosomiasis among children in the Salamat Region of Chad, a previously uninvestigated rural area.

Methods: After discovery of an index case of schistosomiasis in 2014, local villages began requesting screening from a small mobile medical team led by an expatriate American pediatric emergency medicine physician. Each high-risk village was screened by inspecting the urine of 10-50 children for hematuria. If greater than 30% gross hematuria rates were obtained, every child in the village was offered treatment in accordance with WHO guidelines. Patients’ age, height, BMI, and reported hematuria were recorded. Eligible patients were treated with praziquantel. Dosing was determined based on the height-based WHO praziquantel tablet pole with a goal dose of 40 mg/kg. Deidentified data were analyzed using descriptive statistics. Actual weight-based dosing was later assessed to evaluate the accuracy of the WHO tablet pole.

Results: A total of 56 different villages underwent both screening and treatment, of which 11% (n=6) received a second treatment in a subsequent calendar year. There were a total of 11,832 patient encounters and 91% (n=10,780) were eligible for treatment with praziquantel (Figure 1). Among patients, mean age was 7.9 years (SD 4.4); 55% (n=6,466) were male, 41% (n=4,806) were female, and 4% (n=559) were not recorded; 55% (n=6,495) reported hematuria, 34% (n=4,041) denied hematuria, and 11% (n=1,296) had unknown hematuria status. The reported hematuria rate was higher in males (61%, n=3,955/6,466) than females (48%, n=2,301/4,806) (Figure 2). Reported hematuria increased with age, with a prevalence greater than 65% in all age groups over 10 years (Figure 2). Of our study participants, 68% (n=8,025) had a BMI below 15. Within this population, the height-based WHO tablet pole determined effective dosing in 98.4% (n=10,566/10,735) of those patients with sufficient data to calculate mg/kg dosing.

Conclusions: Schistosomiasis is endemic in the Salmat Region of Chad, Africa. Our data highlight the need for continued local epidemiologic efforts required to treat the substantial number of children affected with schistosomiasis, which if left untreated, leads to chronic genitourinary symptoms and complications.