Global Shifts in transfusion-dependent thalassemia (TDT): Epidemiological trends, regional disparities, and prevention strategies (pre-2010 vs. 2015–2021)

Abstract

The global epidemiology of β-thalassemia major has shifted considerably over recent decades, reflecting the success and limitations of prevention programs across regions. Mediterranean nations such as Cyprus, Greece, and Italy have markedly reduced affected births through universal carrier screening, premarital counseling, and accessible prenatal diagnostics, providing effective models for high-prevalence regions. In contrast, South Asian countries including India and Pakistan continue to face a substantial disease burden due to high consanguinity rates, inadequate public health infrastructure, and limited access to genetic services. Although incidence is declining in Southeast Asia, particularly in Thailand and China, the large population base sustains a significant absolute number of cases. New clusters are emerging in Northern Europe and Latin America as a consequence of migration from endemic areas, underscoring the need to adapt screening and counseling programs even in historically low-prevalence regions. In North Africa, notably Egypt, moderate increases are reported, especially in underserved rural communities where screening access is restricted. The global carrier state varies widely, ranging from <1% in non-endemic areas to >10–14% in South Asia, the Mediterranean, and the Middle East. Addressing these disparities requires region-specific strategies combining community-based education, culturally sensitive counseling, premarital or antenatal screening, and integration of genetic services into primary healthcare systems.