Newborn screening for sickle cell disease in Angola: Implementation challenges and emerging data on hemoglobinopathy prevalence

Sickle Cell Disease (SCD) is an autosomal recessive disorder with a substantial global burden. Despite its particularly high incidence in sub-Saharan Africa, early diagnosis remains limited in many countries. The objective of this study was to implement a newborn screening programme for SCD in one of the largest maternity hospitals in Angola and to support the subsequent pediatric follow-up of the affected children. Between June 2023 and December 2024, all children born in or attending the main hospital for vaccination were screened after parental or guardian consent. Blood was collected by heel-prick onto filter paper, and haemoglobin electrophoresis was performed by isoelectric focusing. Samples identified as HbSS were confirmed by PCR-RFLP, and atypical electrophoretic patterns were further analysed by DNA sequencing. In a total of 13,256 samples analysed the prevalence of HbSS was 1.38% (n = 183), and 20.31% (n = 2692) were HbAS. Other variants identified (n = 44) included HbE, HbC, and α-globin gene alterations. Of the infants diagnosed with SCD, 106 (58%) families were successfully contacted, but only 76 (42%) children initiated regular medical follow-up and prophylactic treatment (penicillin, multivitamins, and vaccinations. 30 families (28%) declined treatment and just one declined follow-up. These findings confirm the high prevalence of SCD in Angola and demonstrate the capacity of newborn screening programmes in reducing early morbidity and mortality. However, the substantial proportion of families refusing follow-up highlights the need for strengthened community health education to improve understanding of SCD.