ABSTRACT
Zoonoses comprise the most significant group of communicable diseases and this emphasizes their prime importance in public health. Most zoonoses are more influenced by geomedical factors other than the wind. Trematodes, such as the cattle fluke and the lancet fluke, are dependent on snails for their development. The lancet fluke, Dicrocoelium lanceolatum, lives in the temperate zone of the Northern Hemisphere. Bilharzia or schistosomiasis is widely distributed in the tropics and does much harm to man and animals. Cestodes or tape worms are dependent on one or more intermediate hosts in their development and they may require special geophysical conditions. Some Protozoa are pathogenic to man and animals and are included among the zoonoses. Many virus diseases are zoonoses. The geomedical interest in viruses is small, compared to that in worms. Bacteria-produced diseases possibly represent the greatest group of all zoonoses.
