Estimating the burden of [alpha]-thalassaemia in Thailand using a comprehensive prevalence database for Southeast Asia

Severe forms of [alpha]-thalassaemia, haemoglobin H disease and haemoglobin Bart's hydrops fetalis, are an important public health concern in Southeast Asia. Yet information on the prevalence, genetic diversity and health burden of [alpha]-thalassaemia in the region remains limited. We compiled a geodatabase of [alpha]-thalassaemia prevalence and genetic diversity surveys and, using geostatistical modelling methods, generated the first continuous maps of [alpha]-thalassaemia mutations in Thailand and sub-national estimates of the number of newborns with severe forms in 2020. We also summarised the current evidence-base for [alpha]-thalassaemia prevalence and diversity for the region. We estimate that 3595 (95% credible interval 1,717--6,199) newborns will be born with severe [alpha]-thalassaemia in Thailand in 2020, which is considerably higher than previous estimates. Accurate, fine-scale epidemiological data are necessary to guide sustainable national and regional health policies for [alpha]-thalassaemia management. Our maps and newborn estimates are an important first step towards this aim.