Australian Meningococcal Surveillance Programme annual report, 2012

In 2012, there were 208 laboratory-confirmed cases of invasive meningococcal disease (IMD) analysed by the National Neisseria Network, and 222 cases notified to the National Notifiable Diseases Surveillance System, thus laboratory data were available for 93.7% of cases of IMD in Australia in 2012. Isolates of Neisseria meningitidis from 116 invasive cases of meningococcal disease were available for testing, and the phenotype (serogroup, serotype and serosubtype) and/or genotype, and antibiotic susceptibility were determined. Molecular typing was performed for the 92 cases confirmed by nucleic acid amplification testing (NAAT). Typing information was available for 194 of the 208 laboratory confirmed cases and 83% (161 cases) were serogroup B infections, 5.7% (11 cases) were serogroup C infections, 3.6% (11 cases) were serogroup W135, and 7.7% (15 cases) were serogroup Y meningococci. The number of laboratory confirmed IMD cases in 2012 was the lowest since laboratory surveillance data have been reported. Primary and secondary disease peaks were observed in those aged 4 years or less and in adolescents (15-19 years) and young adults (20-24 years), respectively. Serogroup B cases predominated in all age groups and jurisdictions. In 2012, the most common porA genotype circulating in Australia was P1.7-2,4. Serogroup C, W135 and Y cases were numerically low, similar to previous years. Decreased susceptibility to the penicillin group of antibiotics was observed in 81.9% of isolates, and 1 isolate exhibited resistance to penicillin. All isolates remained susceptible to ceftriaxone, ciprofloxacin and rifampicin.