The data were entered into Microsoft Excel version 2016, then exported and analyzed using SPSS version 20. Quantitative variables were described using the mean and standard deviation if their distribution was normal, or by the median and interquartile range if the distribution was skewed. Qualitative variables were presented as frequencies and percentages. The comparison of qualitative variables was performed using the Chi-square test or Fisher’s exact test if the conditions for applying the Chi-square test were not met.

The study received approval from the medical and scientific management of the hospital and from the head of the neonatal unit prior to its commencement. Informed parental consent was obtained (using a consent form that was read and signed by the parents of the newborns) before screening each newborn. The study was conducted with respect for patient anonymity to ensure medical confidentiality.

A total of 974 newborns were screened out of 1500 admitted during the study period. The parents were 46.5% Mandé and Gour people from the Northwest and Central-West regions. Fathers worked in the informal sector in 52% of cases, while 61% of mothers did. Maternal electrophoresis results were normal in 60%; the abnormal forms were AS (14%), SC (4%), and SSFA2 (2%). The fathers’ status was unknown in 87% of cases, normal in 4%, with other abnormal forms being AS (6%), SSFA2 (2%), and SC (1%). The majority of newborns, 77%, were born at term.

Family consanguinity was identified in 12% of parents. There was a history of sickle cell disease in siblings in 13% of cases. The main causes of hospitalization included neonatal bacterial infections (30%), anoxic-ischemic encephalopathy (23%), prematurity (21%), and malaria (18.5%).

The rapid diagnostic test for sickle cell disease was normal (AA) in 64% of cases. The sickle cell statuses were AS (14%), AC (8%), SC (6%), SS (6%), and CC (2%).

Using the GAZELLE method, hemoglobin electrophoresis results were normal (AA) in 67.4% of cases; the sickle cell statuses were AS (15.5%), AC (7.7%), SSFA2 (6.4%), SC (2%), and SAFA2 (1%).

The condition of newborns during hospitalization improved favorably in 90% of cases, with a mortality rate of 9%. During the follow-up in the three months following hospitalization, 57% of newborns presented with anemia. Folic acid was prescribed in 98% of cases for these newborns.

There was a significant association between electrophoretic status and mortality. Newborns with an AS electrophoretic profile had a significantly higher risk of death compared to those with a normal electrophoretic status (see Table 1 ). Additionally, there was a link between electrophoretic status and neonatal bacterial infection. Newborns with AS, SAFA2, and SSFA2 statuses had a significantly higher risk of presenting with neonatal bacterial infections (see Table 2 ).

Note: Newborns with an AS electrophoretic profile had a significantly higher risk of death compared to those with a normal electrophoretic status (p = 0.0002).

Note: Newborns with AS, SAFA2, and SSFA2 electrophoretic statuses had a significantly higher risk of presenting with neonatal bacterial infections (p < 0.0001).

We investigated 974 newborns, of whom 318 were carriers of sickle cell disease, resulting in a prevalence of 32.6% (AS (15.5%), AC (7.7%), SSFA2 (6.4%), SC (2%), and SAFA2 (1%)). This figure was slightly higher than that reported by Cabannes et al. [5] , who noted a general prevalence of 12 to 14% in Côte d’Ivoire. This difference may be attributed to the fact that our prevalence is hospital-based and monocentric, whereas Cabannes reported a national prevalence. In Senegal, out of 3496 newborns screened, 3180 were healthy and not carriers. 316 were carriers of the hemoglobin S gene representing a prevalence of 9% [6] . The predominance in the northern region could be explained by the high migration from the north to the south in search of employment [7] . The previous politico-military crisis in Côte d’Ivoire, particularly in the northern region, caused massive population displacement toward the south to escape the hostilities of war, which could also account for the high number of people originally from the north [8] . Additionally, this result may also reflect a higher practice of endogamy within this population group [8] .

The sickle cell forms identified included AS (60 individuals, 6%), SSFA2 (15 individuals, 2%), and SC (6 individuals, 1%). Among the phenotypes, AS was the most commonly found in our sample, with proportions of 14% in mothers and 6% in fathers, followed by SC and SSFA2 forms. In Mali, among 2489 newborns, 16 were diagnosed with major sickle cell disease (6 SS and 10 SC); 198 had the sickle cell trait, 139 were AC, and 1 was CC [9] . In this study involving 2420 mothers whose children underwent neonatal screening for sickle cell disease, the frequency of abnormal electrophoretic profiles was found to be 21.3% [9] . In another study, 143 children were heterozygous (15.10%) and 17 were homozygous (1.80%) [10] . Conversely, in Ouagadougou, the hospital frequency of major sickle cell disease among children aged 0 to 15 years was reported as 1.67% in pediatric admissions [11] . The very high proportion of unknown electrophoresis results (87% in fathers) compared to mothers (11%) could be explained by the lack of routine electrophoresis in standard examinations and premarital screening. However, this test is a key recommended part of prenatal assessment for all pregnant women, which may account for the higher unknown results among fathers.

Regarding consanguinity, 12% of parents reported a family history of consanguinity. This finding is lower than that of Aka Tanoh [12] , who found that 24.7% of children were from consanguineous marriages. This difference may be due to the fact that previous studies primarily focused on known sickle cell children, whereas our study involved newborns whose electrophoretic status was initially unknown.

In our study, 65 couples (13%) had at least one child with sickle cell disease. Our results are lower than those of Eloundou [13] , who found a 35% occurrence in cases with at least one sibling affected by the disease. This difference could be attributed to the fact that the family history of sickle cell disease was unknown in the majority of cases in our study, leading to underestimation.

Most newborns (746, or 77%) were aged between 0 and 10 days. Anemia was likely related to complications from prematurity or often an infectious pathology. The incidence of neonatal bacterial infection is even higher in premature infants than in full-term newborns [14] . Anemia in general is defined as a decrease in the total amount of circulating hemoglobin (Hb), and more specifically, it corresponds to an Hb level less than −2 standard deviations (SD) from the mean for the age. All newborns experience a decrease in Hb levels known as “physiological anemia.” This decrease varies between 9.5 and 11 g/dL around 10 - 12 weeks of age in full-term newborns. In contrast, premature infants experience a more severe and earlier form of anemia called “anemia of prematurity” [15] .

The difference observed between the rapid diagnostic tests (RDTs) can be explained by the fact that the primary aim of the rapid diagnostic test is to screen for sickle cell disease (a hemoglobinopathy) with results being qualitative (presence or absence). It is based on an immunological method to identify the presence of hemoglobins A, S, and C, but it cannot determine thalassemia. In contrast, the GAZELLE method is quantitative and also enables the determination of thalassemia [16] . The Sickle SCAN and hemoType SC RDTs are sensitive and specific for identifying newborns with a sickle cell phenotype. They meet the quality criteria for RDTs aimed at the diagnostic orientation of sickle cell disease and are particularly useful in endemic countries where access to laboratory equipment is severely limited [4] .

There exists a correlation between electrophoretic status and mortality. Newborns with an AS electrophoretic profile had a significantly higher risk of death compared to those with a normal electrophoretic status. Most in-hospital deaths occurred within the first few days of admission, which could be attributed to poor condition at admission or inappropriate evacuation conditions relative to the clinical state of the sometimes premature newborns. Additionally, neonatal bacterial infection was the primary reason for hospitalization. The existence of a causal link between neonatal bacterial infection and AS, SAFA2, and SSFA2 electrophoretic profiles warrants confirmation through larger sampling.