Koro (medicine) - Epidemiology

Epidemiology

Among the Chinese, koro is confined to South China and the lower Yangtze Valley. A 1992 study of self-report questionnaires suggests that in the epidemic area of China, koro victims are mostly Han, male, young, single, poorly educated and fearful of supernatural forces and koro. The phenomenon is also found among oversea Chinese in Southeast Asia, especially Malaysia and Indonesia, and less frequently among the Malay and Indonesian inhabitants of the countries. Though there are speculations that the occurrence of koro among people in Malaysia and Indonesia was the result of Chinese migrants, this cultural diffusion view is challenged since koro epidemics have been reported in Thailand and India, involving masses of non-Chinese people.

Sporadic cases of koro among people with non-Southeast-Asian ethnicity have been reported across the globe, for example, Nepali, Sudanese, Jordanian, Tanzanian, Nigerian, French, British, American and Canadian. In most of the non-Chinese cases in the Western hemisphere, genital shrinkage is reported but not all the other typical koro symptoms, such as fear of death, as in endemic countries. The incomplete forms of koro are regarded as the non-cultural forms, while the complete form with acute anxiety is the classical culture-bound type.