| Variables | Definitions |
| , , , and | Number of susceptible, exposed, infected, and removed humans, respectively | , , and | Number of susceptible, exposed, and infected dogs, respectively | , , and | Number of susceptible, exposed, and infected sheep, respectively | | The concentration of Echinococcus granulosusā eggs in the environment | , , and | Total number of dogs, sheep, and humans, respectively |
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