[1] Univ Yaounde I, Serv Hematol & Transfus Sanguine, Ctr Hosp & Univ, Yaounde, Cameroon
[2] Univ Yaounde I, Fac Med & Sci Biomed, Yaounde, Cameroon
[3] Univ Calif San Francisco, San Francisco, CA 94143 USA
[4] Blood Syst Res Inst, San Francisco, CA USA
[5] Univ Paris 05, Inst Natl Transfus Sanguine, Paris, France