Sickle cell disease is an inherited hemoglobinopathy associated with significant morbidity and mortality. Reports suggest a high sickle cell disease burden among the indigenous Tharu population of Nepal, who for centuries have inhabited regions where malaria is endemic. Unfortunately, health care resources are limited and often inaccessible for Tharu individuals suffering from sickle cell disease. We conducted a large-scale screening effort to estimate the prevalence of Hb S (HBB: c.20A>T) among the Tharu population and delivered community-based education sessions to increase sickle cell disease awareness. A total of 2899 Tharu individuals aged 6 months to 40 years in the rural district of Dang in Western Nepal were screened using a sickling test, of whom, 271 [9.3%; 95% confidence interval (95% CI): 8.3-10.4%] screened positive for Hb S. Those who screened positive were offered diagnostic gel electrophoresis testing. Of the 133 individuals who underwent diagnostic testing, 75.9% (n = 101) were confirmed to be Hb AS heterozygotes, 4.5% (n = 6) were confirmed to be Hb SS homozygotes and 19.5% (n = 26) were false positives. These findings support a large burden of sickle cell disease among the Tharu population and highlight the importance of appropriate resource allocation and management. With a positive predictive value of 80.0% (95% CI: 73.0-87.0%), the sickling test in conjunction with raising local sickle cell disease awareness may be a simple and sustainable way to promote access to health resources.
Keywords: Hemoglobinopathy; Nepal; sickle cell anemia; sickle cell disease; sickle cell trait.