Received: 30 September 2019
Accepted: 16 October 2019
First Online: 29 October 2019
Ethics approval and consent to participate
: The study was reviewed and approved by the University of Gondar ethical committee (O/V/P/RCS/05/360/). Each study participant was informed about the objective of the study that contributes necessary information for policymakers and other concerned bodies. Informed written consent was obtained from study subjects before we asked them to give a sample. Participants were informed that they have the full right to continue or withdraw from the study at any time and all the information and results of the study subject would be kept confidentially.
: Not applicable.
: The author(s) declare(s) that there is no conflict of interest regarding the publication of this paper.