In general, the intermediate host shows many more signs of illness than the definitive host. Because the eggs are often released from the segments before the segments pass out through the feces, the main method of diagnosis is through microscopic fecal examination. All Taenia eggs look alike and are identical to those of Echinococcus . Prevention methods must be based on prohibiting dogs and cats from eating raw meat or offal , and preying on wild animals. The immature forms in the intermediate hosts are killed by freezing or cooking.
Rodent control is important.
Dogs and wild canids serve as the definitive hosts of Echinococcus granulosus . Herbivores such as sheep are the intermediate hosts. Fox, cats, and dogs are definitive hosts for E. multiocularis , and voles, lemmings and shrews serve as the intermediate hosts. Humans can also serve as intermediate hosts for both species of Echinococcus . Both of these tapeworms are found in limited areas in North America.