Received: 5 July 2020
Accepted: 28 October 2020
First Online: 7 November 2020
Ethics approval and consent to participate
: This study was reviewed and approved by the National University Biomedical Research Ethics Committee, National University-Sudan. Oral and written informed consents were obtained from participants’ or parents or guardians in case of children.
: Not applicable.
: The authors declare that they have no competing interests.