Burden of antimicrobial resistance in the WHO Southeast Asia and Western Pacific Regions, 1990–2021: a cross-country systematic analysis with forecasts to 2050

Abstract

<p><b>Background </b><br></p><p>Antimicrobial resistance (AMR) constitutes a critical global health challenge with major implications for public health and economic stability, increasing infection- and sepsis-related mortality. Despite growing evidence on its contribution to disease burden, comprehensive assessments of long-term trends at the regional level remain limited in the World Health Organization (WHO) Southeast Asia Region (SEAR) and Western Pacific Region (WPR). <br></p><p><b>Methods </b><br></p><p>We used data from the Global Research on Antimicrobial Resistance (GRAM) Project to evaluate sepsis- and AMR-related deaths and disability-adjusted life-years (DALYs) for 11 infectious syndromes, 22 pathogens, and 84 pathogen-drug combinations across 42 countries and territories in the WHO SEAR and WPR from 1990 to 2021. AMR burden was estimated under two counterfactual scenarios: deaths and DALYs attributable to AMR (representing the burden if drug-resistant infections were replaced by drug-susceptible infections), and deaths and DALYs associated with AMR (representing the burden if infections did not occur at all). We reported numbers, crude rates, and age-standardized rates, and generated forecasts of AMR burden to 2050 using an autoregressive integrated moving average model. <br></p><p><b>Results</b><br></p><p> In SEAR and WPR, there were 8.36×106 [95% uncertainty interval (UI) 7.93–8.79] sepsis-related deaths in 1990, which decreased to 6.03×106 (95% UI 5.68–6.39) in 2019 before increasing to 8.31×106 (95% UI 7.86–8.76) in 2021. The number of deaths associated with AMR ranged from 2,445,875 (95% UI 2,221,769–2,670,192) in 1990 to 2,358,190 (95% UI 2,173,521–2,545,190) in 2021, while deaths attributable to AMR ranged from 546,479 (95% UI 487,669–605,277) to 587,103 (95% UI 534,165–639,903) over the same period. From 1990 to 2021, deaths attributable to AMR decreased among people <25 years, with a 76.1% [95% confidence interval (CI) 70.6–81.6] reduction occurring among children <5 years, while those among adults aged ≥70 years more than doubled, increasing from 133,013 (95% UI 124,066–141,922) to 298,366 (95% UI 284,023–312,475). The largest increase in the number of deaths attributable to AMR was caused by methicillin-resistant Staphylococcus aureus [from 30,168 (95% UI 24,956–35,351) in 1990 to 66,946 (95% UI 57,544–76,479) in 2021]. In 2021, Kiribati had the highest age-standardized mortality rate (per 100,000 person-years) attributable to AMR [30.9 (95% UI 24.1–37.8)], whereas New Zealand had the lowest [3.2 (95% UI 2.6–3.8)] among the two regions. By 2050, the number of deaths associated with AMR is predicted to reach 3,875,753 (95% UI 1,502,402–9,998,297) in these two regions, of which 952,592 (95% UI 766,353–1,184,090) deaths are attributable to AMR. <br></p><p><b>Conclusions </b><br></p><p>This study highlights the escalating burden of AMR in SEAR and WPR, emphasizing the urgent need for attention to this persistent and growing crisis. Our analyses underscore the dual challenge of sustaining gains among people <25 years while addressing the alarming increase of AMR in elderly populations. Given the high variability of AMR burden by pathogen, age group, and country, strengthened surveillance and improved laboratory capacity are essential to accurately characterize resistance patterns and guide clinical decision-making.</p>