Testicular immunology
Mumps is a viral disease which causes swelling of the salivary glands and testes. The mumps virus lives in the upper respiratory tract and spreads through direct contact with saliva. Prior to widespread vaccination programs, it was a common childhood disease. Mumps is generally not serious in children, but in adults, where sperm have matured in the testis, it can cause more severe complications, such as infertility.
Joint Committee on Vaccination and Immunisation
The JCVI has firmly endorsed the efficacy and safety of the MMR vaccine. Among many developments, in February, 1988, fifteen experts and officials met in the UK to discuss adverse events reported after the administration of the vaccines which contained the attenuated Urabe mumps virus strain. According to JCVI's minutes, the group "read a report of cases of mumps encephalitis which had been associated with MMR vaccine containing the Urabe strain of the mumps virus."