Prevalence of Thalassemia among Newborns: A Re-visited after 20 Years of a Prevention and Control Program in Northeast Thailand

Background. To provide accurate prevalence information of thalassemia in northeast Thailand, authors performed thalassemia screening in newborns after 20 years implementation of a prevention and control program. Methods. Study was done on 350 cord blood specimens collected consecutively at Maternal and Child Hospital, Regional Health Promotion Center 7, Khon Kaen, Thailand. All kinds of alpha- and beta-thalassemias were identified using combined hemoglobin (Hb) and DNA analyses. Results. Among 350 newborns examined, subjects with thalassemia genes were identified in 184 (52.6%) cases with as many as 22 different genotypes. The most prevalent one was Hb E (39.1%). The incidence of 3.1% alpha(0)-thalassemia, 25.9% alpha(+)-thalassemia, 5.4% Hb Constant Spring and 1.4% of Hb Pakse were encountered. Heterozygous beta-thalassemia was found in 2 cases (0.6%). Hb capillary electrophoresis could demonstrate Hb E in all cases with Hb E and detected different levels of Hb Bart's for different alpha-thalassemia genotypes but not in all cases with a-thalassemia. No newborn with severe thalassemia diseases was encountered. Conclusion. This study reveals that alpha-thalassemia, beta-thalassemia, and Hb E carriers as well as complex thalassemia syndromes are still prevalence and indicates a need for continuing a prevention and control program in the region.