This article has been retracted: please see Elsevier Policy on Article Withdrawal (withdrawalpolicy).
This abstract has been retracted at the request of Editor-in-chief and the publisher.
The authors have plagiarized part of a paper that had already appeared in Pan Afr Med J. 2018; 31: 29. Doi:10.11604/pamj.2018.31.29.16354. One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.Le texte complet de cet article est disponible en PDF.