There are three main species of schistosoma which is the parasite can cause bilharzia.
Schistosoma mansoni is distributed in Africa, Middle East, several countries of south America and some of the Caribbean islands.
Schistosoma haematobium is found in Africa and some areas of the Middle East.
Schistosoma japonicum is found in Indonesia, China and parts of southeast Asia.
There are also some species of lesser importance as schistosoma intercalatum which is found in central and West and schistosoma mekongi which is found in Cambodia and Laos.
So, the three continents that were ravaged by bilharzia are Africa, Asia and South America.
