Insights into the burden of bacterial antimicrobial resistance (AMR) in the WHO Eastern Mediterranean Region: a crucial step towards evidence-informed and targeted public health interventions

Abstract

Introduction: Antimicrobial resistance (AMR) is a significant but very complex global health issue, making it difficult to accurately determine its full impact. This study aimed to provide the most detailed regional/national estimates of the AMR burden in the WHO Eastern Mediterranean Region. Methods: To estimate deaths and disability-adjusted life years (DALYs) due to AMR for 23 bacterial pathogens and 88 pathogen-drug combinations for 2019 and for the first two years of the COVID-19 pandemic, we utilized data from mortality registries, surveillance systems, hospital records, literature reviews and other sources. A predictive statistical modeling approach - which included five components (the role of infection in deaths, the attribution of infectious deaths to specific syndromes, the proportion of infectious syndrome deaths attributable to specific pathogens, the percentage of pathogen resistant to antibiotics, and the excess risk of mortality associated with this resistance) - was used to integrate this data. We compared the burden in different time periods, and two counterfactual scenarios have been used: deaths/DALYs attributable to AMR and deaths/DALYs associated with AMR. The models were cross-validated to assess out-of-sample predictive validity. Results: The study found that bacterial AMR imposes a significant burden in the WHO Eastern Mediterranean Region, with an estimated 465,000 deaths (95% UI 338,000–621,000) associated with and 124,000 deaths (133,000–220,000) directly attributable to resistance. Respiratory infections emerged as the most significant cause of fatal AMR burden. Six main pathogens – Klebsiella pneumoniae, Escherichia coli, Streptococcus pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii –accounted for 326,000 deaths associated with AMR. Somalia had the highest AMR burden, with 62.9 deaths (37.4–107.5) attributable to and 223.1 deaths (159.6–309.6) associated with AMR per 100,000 population; conversely, Tunisia had the lowest, with 8.5 deaths (5.1–13.4) attributable to and 34.0 deaths (20.5–53.3) associated with AMR per 100,000 population. The leading pathogen-drug combination burden-wise was methicillin-resistant Staphylococcus aureus, with many other prominent ones. A higher AMR burden was observed in nations with a lower Socio-demographic Index (r = –0.87 [–0.9 to –0.83]). Changes in burden occurred during time, with shifts in leading pathogens during the first two years of the COVID-19 pandemic. Discussion: The substantial number of deaths associated with bacterial AMR underscores the significant public health threat. The high burden observed in countries like Somalia suggests that resource-limited settings may be particularly vulnerable, indicating a need for targeted resource allocation. The predominance of respiratory infections as a prime contributor to AMR-related mortality unveils the need for improving diagnostic/treatment protocols; likewise, time trends and underlying socioeconomic disparities have to be taken into account. Conclusion: To effectively combat AMR in the WHO Eastern Mediterranean Region, strategies must be tailored and targeted to address the specific characteristics of the predominant pathogens and the most critical pathogen-drug combinations.