Received: 24 May 2020
Accepted: 26 June 2020
First Online: 6 July 2020
Ethics approval and consent to participate
: The study ethical clearance was obtained from University of Khartoum, Faculty of Medical Laboratory Sciences ethical review board. Informed consent was obtained from each participant prior to enrollment using writing and verbal informed consent.
: Not applicable.
: The authors declare that they have no competing interests.