Type B and C are predominant in Asia; type D is common in the Mediterranean area, the Middle East and India; type E is localized in sub-Saharan Africa; type F (or H) is restricted to Central and South America.
Tipe B dan C mendominasi di Asia; tipe D umum ditemukan di wilayah Mediterania, Timur Tengah, dan India; tipe E terlokalisasi di Afrika sub-Sahara; tipe F (atau H) terbatas pada Amerika Selatan dan Tengah.