Regional and national burden and etiological patterns of diarrheal disease in Asia with implications for travel medicine

BACKGROUND: Despite the considerable burden of diarrheal disease in Asia, etiology-specific patterns remain insufficiently characterized. This study aimed to provide a comprehensive assessment of the diarrheal disease burden across Asia from 1990 to 2023, focusing on the implications for travelers' diarrhea. METHODS: We estimated the burden of diarrheal disease in Asia, including Central, East, South, Southeast Asia, and High-income Asia Pacific, across 34 countries from 1990 to 2023 using the Global Burden of Diseases Study 2023. Disease burden was calculated using age-standardized disability-adjusted life year rates (ASDRs) per 100,000 population, with 95% uncertainty intervals (UIs). Additionally, we assessed the burden attributable to risk factors and calculated pathogen-specific estimates for 13 major etiologies. RESULTS: From 1990 to 2023, ASDRs of diarrheal disease declined across Asia, with the largest decline in South Asia from 9124.29 (95% UI, 7594.46-11,673.82) per 100,000 population to 1216.90 (965.73-1633.55). The decline was accompanied by reductions in cumulative etiologic burden, particularly for rotavirus. Although norovirus was the leading etiology in High-income Asia Pacific, rotavirus remained dominant across all other Asian regions in 2023. Burdens were concentrated among those aged <5 years and ≥95 years. Among children aged <5 years, rotavirus and adenovirus were the leading etiologies, with adenovirus showing a particularly high age-specific DALY rate in South Asia (891.96 [484.65-1392.81] per 100,000 population). Among adults aged ≥ 95years, Clostridium difficile and norovirus had the highest burdens. Sex-specific burdens were generally higher in males, except in South Asia. In 2023, unsafe water sources were the leading risk factor, especially in South Asia, 831.77 (423.32-1206.25) per 100,000 population. For viral, parasitic, and gram-negative etiologies, burdens consistently declined with increasing SDI, whereas Clostridium difficile showed a U-shaped pattern with SDI. CONCLUSIONS: The heterogeneity in etiology-specific burden, age- and sex-related vulnerability, and associations with SDI across Asia underscores the need for destination-specific risk assessment and context-sensitive prevention strategies for travelers' diarrhea in Asia.