Funding for this research was provided by:
Received: 1 September 2017
Accepted: 8 January 2018
First Online: 24 January 2018
Ethics approval and consent to participate
: The study was conducted under the ethical clearance No. 2016/11/832/CE/CNERSH/SP delivered by the Cameroon National Ethics (CNE) Committee for Research on Human Health Ref No. 0977/A/MINSANTE/SESP/SG/DROS of 18 April 2012. The study did not use any human subject.
: Not applicable.
: The authors declare that they have no competing interests.
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