A Prospective Pilot Newborn Screening and Treatment Program for Sickle Cell Anemia in the Republic of Angola

Sickle cell anemia (SCA) is a significant global health problem with >300,000 affected infants born each year in sub-Saharan Africa. Up to 80–90% of all children with SCA in Africa die before five years of age, due to infection or anemia, and usually without the proper diagnosis of SCA. Early identification by newborn screening (NBS), followed by interventions such as pneumococcal immunization and prophylactic penicillin, have dramatically reduced the mortality of children with SCA in the US, but this strategy not yet been established in Africa. A novel public-private partnership involving the Republic of Angola, Chevron Corporation, and Baylor College of Medicine/Texas Children's Hospital was created to develop a pilot NBS and treatment program for SCA, focusing on capacity building and local ownership.

Two large maternity hospitals in the capital city of Luanda, Angola were initially selected for dried blood spot (DBS) collection and analysis, and a third local health center was soon added. Maternity nurses were taught DBS collection and laboratory technicians learned isoelectric focusing (IEF) and capillary electrophoresis (CE) techniques. Identifiers including cell phone numbers are collected onto the Whatman NBS card to facilitate retrieval of affected babies. After collection, DBS were transported to the central NBS laboratory at Hospital Pediátrico David Bernardino (HPDB) for hemoglobin identification by IEF and CE. Demographic data and test results were entered into a unique internet-based electronic data capture system designed with secure password-protection and servers located in Houston, Texas.

Since initiation of NBS in July 2011, 17,055 babies have DBS collection and laboratory results: 3,588 (21%) with FAS pattern (sickle cell trait), and 264 (1.55%) with FS (consistent with SCA). Twenty-one samples produced a result other than FA, FAS, or FS, including 10 FAC and 1 FSC. Families of infants with an FS screening result are notified by phone to initiate care and treatment, ideally by age 8 weeks. In the new infant SCA clinic at HPDB, infants receive penicillin prophylaxis and PCV-13 pneumococcal immunization, while parents receive sickle cell education and insecticide-treated bed nets for malaria protection. In the first 6 months, 67.8% of DBS cards had phone numbers documented, but with education and reinforcement, 81.4% of cards had phone numbers in the past 6 months. To date, 220 FS babies are age-eligible for contact and 110 (50%) families have been reached: 104 (47%) have come to the infant SCA clinic, 6 (2.7%) had already died within the first month of life, and 0 refused care. A total of 201 doses of PCV-13 have been provided as per routine vaccination scheduling. After initial visit, the return rate for second immunization is 94% with only 3 babies lost to follow-up including 2 deaths. The calculated first-year mortality rate for all contacted FS babies (6.9%) compares favorably to the national infant mortality rate (9.8%).

This prospective pilot study documents that newborn screening for SCA is feasible in a developing country such as Angola. Capacity building and teaching provide local healthcare workers with skills necessary to have a functional NBS program and infant SCA clinic. The sickle cell burden is extremely high in Angola, and contact and retrieval of all affected FS infants remains an ongoing challenge, but families are compliant with clinic appointments and treatment. Early mortality data suggest comprehensive SCA care can save lives, suggesting that expansion of the pilot program is warranted with an eventual national strategy for the diagnosis, care, and treatment of children with SCA in Angola.

No relevant conflicts of interest to declare.