Other symptoms are fever, a general feeling of illness, and pain on chewing or swallowing. Sterility resulting from involvement of the testes and fatalities from the meningoencephalitis occur in a small minority of male cases. Other possible complications include pancreatitis and involvement of the heart or thyroid. The ovaries are sometimes affected in females.
Treatment consists mainly of bed rest, intake of fluids, and the administration of analgesics.
A live virus vaccine has been developed that can be given to susceptible children at 15 months.