Mumps (epidemic parotitis) is a viral disease of the human species, caused by the mumps virus. Before the development of vaccination and the introduction of a vaccine, it was a common childhood disease worldwide. It is still a significant threat to health in developing countries, and outbreaks still occur sporadically in developed countries. Painful swelling of the salivary glands – classically the parotid gland – is the most typical presentation. Painful testicular swelling (orchitis) and rash may also occur. The symptoms are generally not severe in children. In teenage males and men, complications such as infertility or subfertility are more common, although still rare in absolute terms. The disease is generally self-limiting, running its course before receding, with no specific treatment apart from controlling the symptoms with pain medication. Fever and headache are prodromal symptoms of mumps, together with malaise and anorexia.