Received: 12 October 2018
Accepted: 29 January 2019
First Online: 5 February 2019
Ethics approval and consent to participate
: The protocol was approved by the National Ethics Committee for Research in Health in Senegal on 16 December 2014 under no. 377/MSAS/DPRS/CNERS. All parents or guardians provided written informed consent.
: “Not applicable”.
: The authors declare that they have no competing interests.
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