Received: 24 September 2018
Accepted: 14 January 2019
First Online: 1 February 2019
Ethics approval and consent to participate
: Ethical clearance was obtained from the Institution Review Board, Research and Publication Committee of the Muhimbili University of Health and Allied Sciences (MUHAS) and the Director of Medical Services of MNH. We obtained written informed consent from participants’ guardian or parents prior to participation into the study.
: Not applicable.
: The authors declare that they have no competing interests.
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