Epidemiology
The beta form of thalassemia is particularly prevalent among Mediterranean peoples and this geographical association is responsible for its naming: Thalassa (θάλασσα) is the Greek word for sea and Haema (αἷμα) is the Greek word for blood. In Europe, the highest concentrations of the disease are found in Greece, coastal regions in Turkey (particularly the Aegean Region such as Izmir, Balikesir, Aydin, Mugla, and Mediterranean Region such as Antalya, Adana, Mersin), in parts of Italy, particularly Southern Italy and the lower Po valley. The major Mediterranean islands (except the Balearics) such as Sicily, Sardinia, Malta, Corsica, Cyprus, and Crete are heavily affected in particular. Other Mediterranean people, as well as those in the vicinity of the Mediterranean, also have high rates of thalassemia, including people from West Asia and North Africa. Far from the Mediterranean, South Asians are also affected, with the world's highest concentration of carriers (16% of the population) being in the Maldives.
Nowadays, it is found in populations living in Africa, the Americas and also, in Tharu in the Terai region of Nepal and India. It is believed to account for much lower malaria sicknesses and deaths, accounting for the historic ability of Tharus to survive in areas with heavy malaria infestation, where others could not. Thalassemias are particularly associated with people of Mediterranean origin, Arabs (especially Palestinians and people of Palestinian descent), and Asians. The Maldives has the highest incidence of Thalassemia in the world with a carrier rate of 18% of the population. The estimated prevalence is 16% in people from Cyprus, 1% in Thailand, and 3-8% in populations from Bangladesh, China, India, Malaysia and Pakistan. Thalassemias also occur in descendants of people from Latin America and Mediterranean countries (e.g. Greece, Italy, Portugal, Spain, and others).
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