Prevention is related to the cause. Most cases cannot be prevented. However, many can be treated.
If a large amount of swelling is allowed to remain for too long, the skin may break down. Chronic skin changes, skin ulcers, and infections can occur with skin breakdown. However, most long-term effects are related to the cause. For example, liver, heart or kidney diseases can lead to serious disability or even death. Infections of a limb may go away completely and have no long-term effects. In severe cases, however, the limb may need to be amputated.
Swelling of the limbs is not contagious and poses no risks to others.