Mumps is a contagious disease caused by the mumps virus. Mumps typically starts with a few days of fever, headache, muscle aches, tiredness, and loss of appetite, and is followed by swelling of salivary glands. Mumps can be prevented with the MMR vaccine. Before the routine MMR vaccination in the United States, mumps was a common illness in infants, children and young adults. Because most people have now been vaccinated, mumps has become a rare disease in the United States.
Questions and answers about lab testing (CDC site)
Communicable Disease Manual - Mumps
Epidemiology and Prevention of Vaccine-Preventable Diseases: Mumps (CDC, 11th Edition)