Ethiopia: Resistance to a last-resort antibiotic is rising sharply in Africa to two multidrug-resistant (MDR) bacterial pathogens that pose major threats in health care settings, according to a study this week in JAC-Antimicrobial Resistance.
In a systematic review and meta-analysis, researchers from Ethiopia examined 35 studies on reported colistin resistance in clinical specimens of Acinetobacter baumannii and Pseudomonas aeruginosa from Africa. A baumannii and P aeruginosa are already resistant to multiple antibiotic classes and are considered critical- and high-priority pathogens by the World Health Organization. Limited treatment options for MDR A baumannii and P aeruginosa in Africa have led to renewed use of colistin, which had been limited to veterinary use because of its toxicity in humans.
While the emergence of colistin resistance in the two pathogens is being reported “with increasing frequency,” the study authors note, “a comprehensive study that analyses and synthesizes the available evidence on the prevalence of colistin resistance in A. baumannii and P. aeruginosa isolates in Africa is still lacking.”
Of the included studies, 20 investigated A baumannii, 10 assessed P aeruginosa, and five evaluated both organisms. The pooled prevalence of colistin resistance in A baumannii was 13.75%, with variation among countries, ranging from 18.26% in Egypt to 10.89% in South Africa. For P aeruginosa, the pooled prevalence of colistin resistance after adjustments was 14.42%, ranging from 13.55% in Egypt to 1.07% in Ethiopia.
Resistance rose dramatically over time, from 5.64% to 16.45% in A baumannii and from 2.26% to 30.54% in P aeruginosa between 2010–2017 and 2018–2023.
The authors say the increasing prevalence of colistin resistance in Africa has serious implications for antimicrobial therapy strategies and major clinical consequences.
“This threatens the role of colistin as a last-resort therapy and is associated with higher morbidity, mortality and healthcare costs,” the authors wrote. “Urgent action is therefore needed to strengthen antimicrobial stewardship, implement standardized resistance surveillance and reinforce infection prevention and control measures across the region.”
