MUMPS - An infectious acute viral disease affecting the parotid glands. The gonads, meninges, and pancreas can also be affected. The causative agent is a paramyxovirus. Humans are the only natural host for this disease. Common symptoms include weakness, fever, sore throat, malaise, and puffiness to the cheeks (due to parotid gland swelling). Patients are contagious 1 day prior to the onset of swelling until the swelling is gone. Recovery is generally in 2 weeks.