Article History
Received: 14 January 2019
Accepted: 31 January 2019
First Online: 22 February 2019
Ethics approval and consent to participate
: Ethical approval was obtained; <b>REC</b> (University of Nairobi) reference: KNH-ERC/A/289<b>.</b>
: The subjects in Figs. InternalRef removed, InternalRef removed, and InternalRef removed provided written consent for their images to be published.
: The authors declare that they have no competing interests.
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