Meningococcal disease epidemiology in Australia 10 years after implementation of a national conjugate meningococcal C immunization programm

Australia implemented conjugate meningococcal C immunization in

2003 with a single scheduled dose at age 12 months and catch-up for

individuals aged 2–19 years. Several countries have recently added

one or more booster doses to their programmes to maintain disease

control. Australian disease surveillance and vaccine coverage data

were used to assess longer term vaccine coverage and impact on

invasive serogroup C disease incidence and mortality, and review

vaccine failures. Coverage was 93% in 1-year-olds and 70% for

catch-up cohorts. In 10 years, after adjusting for changes in

diagnostic practices, population invasive serogroup C incidence

declined 96% (95% confidence interval 94–98) to 0·4 and 0·6

cases/million in vaccinated and unvaccinated cohorts, respectively.

Only three serogroup C deaths occurred in 2010–2012 vs. 68 in

2000–2002. Four (<1/million doses) confirmed vaccine failures

were identified in 10 years with no increasing trend. Despite

published evidence of waning antibody over time, an ongoing single

dose of meningococcal C conjugate vaccine in the second year of

life following widespread catch-up has resulted in near elimination

of serogroup C disease in all age groups without evidence of

vaccine failures in the first decade since introduction.

Concurrently, serogroup B incidence declined independently by

55%.