The below map from Haseeb and Eveland's section from Fried and Graczyk's text shows the regions where echinostomiasis is most prevalent, with the darker areas showing regions where more echinostome species have been reported, and lighter areas representing regions of less endemicity.
Echinostomes as Experimental Models for Biological Research, p. 88, 2000.
As of 2004, it was estimated that 40-50 million people throughout the world were infected with food-borne trematodes, many of which are echinostomes, and that more than 10% of the world was potentially at risk for infection (Fried, Graczyk, and Tamang 2004).
Endemic areas of echinostomiasis include Japan, the Philippines, Malaysia, Sumatra, Java, Sulawesi, India, and other places in southeast Asia and the Far East, with some possible cases from East Africa (John and Petri). The disease is most prevalent in those areas where snails, fish and other possible intermediate hosts are eaten raw. According to Bandyopathy and Nandy's 1986 study, transmission and natural reservoirs exist over widespread regions and are "linked to fresh- or brackish water molluscs...fish, crustaceans, and amphibians (tadpoles or frogs) which constitute a substantial portion of the diet in endemic areas" (qtd. in Fried, Graczyk, and Tamang 2004).
Within the last decade, reports have been made claiming the prevalence of infection with echinostomiasis to be at levels as high as 44% in the Philippines and 50% in norther Thailand, and as low as 5% in mainland China and 9% in Korea (Fried and Graczyk 1998).
The most common species infecting humans tend to include E. ilocanum, E. malayanum, and E. revolutum, but others have been known to reach high levels of endemicity as well (Haseeb and Eveland).