Meningococcal C Disease Outbreak Caused by Multidrug-Resistant Neisseria meningitidis, Fiji

We describe an outbreak of invasive meningococcal disease (IMD) caused by Neisseria meningitidis serogroup C in Fiji. We created surveillance case definitions and collected data by using standard investigation forms. Bacterial identification, antimicrobial susceptibility testing, and PCR were performed in Fiji. Molecular testing was conducted at the Microbiological Diagnostic Unit in Melbourne, Victoria, Australia. During January 2016–December 2018, a total of 96 confirmed or probable IMD cases were reported. Of case-patients, 61.5% (59/96) were male and 38.5% (37) female, 84.4% (81) were indigenous people of Fiji, and 70.8% (68) were children <15 years of age. Annual incidence increased from 1.8/100,000 population in 2016 to 5.2/100,000 population in 2018. Serogroup C multilocus serotype 4821 that is resistant to ciprofloxacin was prevalent (62.1%, 41/66). Public health measures, which included targeted mass vaccination with monovalent meningitis C vaccine, were effective in controlling the outbreak. We observed a rapid decline in meningitis C cases in subsequent years.