The 2004 mumps epidemic among university students questioned the wisdom of vaccinating young children against what is usually a mild, often symptomless childhood infection. Is it possible that the MMR jab had prevented or reduced the students’ chances of catching mumps when young? Had the unnatural immunity conferred by vaccination worn off, exposing the young adults to what, for them being older, had become a more dangerous illness? Catching mumps after puberty is a serious and distressing matter. The testes and ovaries are attacked, resulting sometimes in sterility. Mumps in students used to be rare. There were only ten cases in 1996, before an MMR’d population of children had grown up. There were an estimated 3,000 cases in 2004.[1]

The UK Department of Health was quick to defend the triple MMR jab, claiming that most of the students concerned had not been given it when younger.[2] This would be astonishing. Although MMR was only introduced in 1988, all children up to school age were given the jab in a catch-up campaign. The first recipients would therefore now be 22 years old. This suggests that either the jab was wholly or partially ineffective, or that any protective effect had worn off.

Earlier official explanations of the ‘teen mumps epidemic’ were more clever. Commenting on the 2003 outbreak in Wales, Dr Roland Salmon,* explained that the teenagers were too old to have received the recommended two doses of MMR, but young enough to have grown up during a period of low mumps incidence, thus escaping infection in childhood.

The other possibility is that vaccinating against mumps has caused it to mutate.[3] Several cases of infection with mumps type G have been identified3 whereas MMR uses a type A strain.

* a consultant epidemiologist at the Cardiff Communicable Disease Surveillance Centre

Ed.- The 2004 measles epidemic was presented as a new phenomenon but ‘teen measles has been rising 30% a year since the late ’90s.