Emergence and spread of antibiotic resistance in West Africa : contributing factors and threat assessment.

The emergence and spread of antibiotic resistance present a major public health issue in both developed (DC) and less developed countries (LDC). Worldwide, its main cause is the uncontrolled and unjustified use of antibiotics. In countries with limited resources, such as West African nations, other features, more specifically socioeconomic and behavioral factors, contribute to exacerbate this problem. The objective of this review is to give an update of the common and specific factors involved in the amplification of antibiotic resistance phenomena in LCD, particularly in West African countries. In particular, some frequent societal behaviors (such as self-medication), inadequate healthcare infrastructure (insufficiently trained prescribers and inadequate diagnostic tools), and an uncontrolled drug sector (antibiotics sold over-the-counter, improperly stored, counterfeit, and/or expired) all strongly promote the emergence of antibiotic resistance. This risk is particularly worrisome for enterobacteriaceae producing extended spectrum beta-lactamases (10 to 100 % of colonizations and 30 to 50 % of infections). A similar trend has been observed for carbapenem resistance in enterobacteriaceae with rates ranging from 10 to 30 % and for methicillin resistance in Staphylococcus aureus, which now exceeds 30 %. These troubling observations call for effective health policies in these regions. These intervention strategies must be integrated and simultaneously target policy makers, prescribers, and users.