Prior to the introduction of immunisation, approximately 85 percent of adults had evidence of past mumps infection. Most infections in those aged under 2 years are subclinical, while those affected in adulthood are more likely to experience severe disease. The peak incidence is in late winter and spring.
Mumps vaccine (as MMR) was introduced to the Schedule in 1990 for children aged 12 to 15 months, with a second dose introduced in 1992 for children aged 11 years. The current two-dose schedule at ages 15 months and 4 years was introduced in 2001 (see Appendix 1 for more information). The last mumps epidemic occurred in 1994.
In 2013, 23 cases of mumps were notified, compared to 26 notifications in 2012 (17 were laboratory confirmed) and 51 notifications in 2011 (24 were laboratory confirmed). The 2012 mumps notification rate was 0.6 per 100,000 population, a significant decrease from 2011 (1.2 per 100,000).2