A research has been done in some areas which contain calcium, like Desa Sukowati and Segoro Madu region and also in areas which do not contain calcium (non calcium) like Desa Abar Abir, and areas surrounding bus station in the orthern part of Surabaya. In the non calcium areas the incidence of Strongyoloidiasis is greater than in the calcium areas. In the calcium areas the incidence of Strongyl…