Article History
Received: 25 June 2018
Accepted: 12 December 2018
First Online: 7 January 2019
Ethics approval and consent to participate
: Ethical clearance was obtained from Institutional Review Board of the University of Gondar. Letter of permission was secured from Amhara regional state health bureau laboratory and Gondar University teaching and referral hospital. The ethics committee that approved our study also confirmed that informed consent to participate was not needed.
: Not applicable.
: The authors declare that they have no competing interests.
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