Text and Data Mining valid from 2019-02-08
Received: 7 March 2018
Accepted: 28 January 2019
First Online: 8 February 2019
Ethics approval and consent to participate
: Approval for the study was obtained from the National Blood Transfusion Center Ethics Committee at Libreville, Gabon (No004_of 21st September 2017). All study participants, parents or guardians of individuals younger than 16 years gave a free written and informed consent according to the Helsinki Declarations.
: Not applicable.
: The authors declare that they have no competing interests.
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