1. Department of Medical Hematology, Brazzaville Teaching Hospital, 13 Avenue Auxence Ikonga, BP 32, Brazzaville, Congo
2. Department of Pediatry, Brazzaville Blanche Gomes Hospital, Sassou Nguesso Boulevard, Brazzaville, Congo
3. Department of laboratory, Brazzaville Teaching Hospital, 13 Avenue Auxence Ikonga, BP 32, Brazzaville, Congo