The scourge can travel with the wind and stay alive in snow. The only real way to stop it is by slaughtering infected animals and burying the carcasses. Humans can carry the virus on their boots or clothes. But unlike mad-cow disease, their health is not threatened by the virus. But the effect on all cloven-footed animals is entirely different.
Animals get blisters on their mouths and feet.
They stop eating. They grow lame and lose weight. They stop producing milk. The disease kills only a small percentage of animals. But they can remain sick forever.