title: Australia's century of meningococcal disease: development and the changing ecology of an accidental pathogen.
abstract: Trends in meningococcal disease (MD) over the 20th century in Australia, as in other industrialised countries, have been characterised by epidemics during the two World Wars, a transient rise in incidence in the 1950s followed by endemic disease, and in the 1980s the emergence of a sustained hypersporadic phase. Epidemics occur at times of social upheaval and among marginalised populations, and resolve when living conditions improve. Periodic serogroup A epidemics have been replaced since the 1950s by endemic disease caused mainly by serogroups B and C meningococci. The current hypersporadic plateau in Australia, as in other industrialised countries, is associated with the intercontinental spread of hypervirulent clones of meningococci. The conjugate serogroup C vaccine has reduced the incidence of MD and carriage rates of serogroup C meningococci. However, the vaccine is expensive and its long-term impact on the emergence of non-vaccine strains and on nasopharyngeal microecology is unknown. A rising incidence of MD should not be viewed as the action of a virulent microbe exploiting a vulnerable population, but as the emergence of an "accidental pathogen" from an evolving host-microbial ecology. While it is essential to monitor the impact of vaccines on this ecology, we must find ways that can optimise our coexistence with microbes.
authors.affiliation: National Centre for Epidemiology and Population Health, Australian National University, Canberra, ACT. mahomed.patel@anu.edu.au
authors.forename: Mahomed S
authors.initials: MS
authors.lastname: Patel
mesh_terms: D001315:Australia / Q000453:epidemiology; D003362:Cost-Benefit Analysis; D018563:Disease Notification; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D008589:Meningococcal Infections / Q000453:epidemiology* / Q000266:history / Q000517:prevention & control; D022401:Meningococcal Vaccines / Q000191:economics* / Q000276:immunology; D009345:Neisseria meningitidis / Q000187:drug effects / Q000472:pathogenicity; D018074:Vaccines, Conjugate
chemical_list: D022401:Meningococcal Vaccines; D018074:Vaccines, Conjugate; C410218:serogroup C meningococcal conjugate vaccine