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.
MMR vaccine controversy
The MMR scare caused a low percentage of mumps vaccination (less than 30%), which resulted in outbreaks in Japan. There were up to 2002 measles-caused deaths in Japan while there were none in the UK, but the extra deaths were attributed to Japan's application of the vaccine at a later age. A spokesman for the Ministry of Health said that the discontinuation had no effect in measles, but also mentioning that there were more deaths by measles while MMR was being used. In 1994 the government dropped the vaccination requirement for measles and rubella due to the 1993 MMR scare. Japan is nowadays the only developed country with large measles epidemics. It has been called a "measles exporter" by the US Centers for Disease Control and Prevention. As another consequence of the scare, in 2003, 7 million schoolchildren had not been vaccinated against rubella.