Prevalence of Sickle Cell Disease, Hemoglobin S, and Hemoglobin C Among Haitian Newborns: Feasibility of Newborn Screening for Hemoglobinopathies in Haiti
Authors: Arty Genevieve , Seth Rotz , Bodas Prasad , De Zen Lucia , Zanolli Francesco Angelo , Dall'Amico Roberto 
Published: October 2019

Abstract
Abstract 4235

Background
In the United States, four decades of advances in the treatment of sickle cell disease have reduced mortality rates of affected children from greater than 50% to well below 5%. The greatest impacts have come from inexpensive, non-burdensome interventions. The effectiveness of these interventions relies on universal newborn screening, case-finding, and targeted intervention. We sought to determine the prevalence of sickle cell disease among Haitian newborns and demonstrate feasibility of a hemoglobinopathy screening effort at a large scale.
Haiti, the poorest country in the Western Hemisphere, lacks newborn screening. One study examined incidence of hemoglobinopathy traits (HbS and HbC) among infants of recent Haitian immigrants in Maimi, FL, USA, and reported an incidence of 8% and 4.7%. The study was limited by small sample size, and a population that might differ from native Haitians. Another study examining the prevalence of sickle hemoglobin among healthy adult volunteers in Northern Haiti, reported at 15.5%. Testing methods did not distinguish trait from homozygous disease, though volunteers were clinically well. In a previously published pilot study, our group sought to address these limitations through direct screening of newborns. We screened 259 newborns. We demonstrated prevalence of S trait, SS disease, and SC disease of 10%, 1.5%, and 1.5% respectively. In this report we present an update and demonstrate the scalability and feasibility of our approach in a much larger population.

Methods
2459 consecutive newborns at Saint Damien Pediatric Hospital in Port-Au-Prince, Haiti in 2010 were screened for detection of hemoglobin types F,A,S,C,D, and E to establish prevalence of Sickle Hemoglobin. Heel-prick specimens were obtained and placed on filter paper (S&S 903, Schleicher & Schuell, New Hampshire, USA) and sent to Pordenone Hospital, Italy. Screening was performed using the Variant HPLC system (Bio-Rad Laboratories, California, USA), then Variant NBS HPLC system (Bio-Rad Laboratories, California, USA). Our project has evolved from screening only, to active case finding and provision of comprehensive disease management. The program is driven by local physician leaders and supported by a multinational team of academic and clinical staff.

Results
Among 2459 screened neonates 2258 specimens were able to be tested. 201 were unable to be tested due to technical issues with samples. Of the 2258 samples tested, 247 had HbS, fifty-seven had HbC, ten had HbSS, and three had HbSC. This yields a prevalence of 10.9%, 2.5%, 0.44% and 0.13% respectively. This corresponds to the prevalence of HbSC or HbSS of one in one hundred seventy three newborns.

Conclusions
Sickle cell disease is highly prevalent in Haiti, warranting universal screening and treatment efforts. We have demonstrated feasibility of newborn screening in Haiti. We recognize that challenges will exist in expanding this project to remote settings. Further, given that 78% of children in Haiti are born outside of hospitals, challenges to screening these patients remain. Nonetheless, this project provides valuable data at a scale suitable to inform clinical decision-making as well as health policy development.

Disclosures:
No relevant conflicts of interest to declare.