Prevalence of Neisseria meningitidis serogroups in invasive meningococcal disease in China, 2010-2020: a systematic review and meta-analysis

Invasive meningococcal disease (IMD) caused by Neisseria meningitidis (Nm) continues to be a global public health concern. Understanding the prevalence of Nm serogroups in IMD is critical for developing strategies for meningococcal vaccination. We used the keywords "cerebrospinal meningitis", "meningococcal", "Neisseria meningitidis'', "meningococcal meningitis", "serogroup'' and "China'' to search five databases, including PubMed, CNKI, CBM (Chinese BioMedical Literature Database), WanFang and VIP from 2010 to 2020. The age distributions, proportions of Nm serogroups and serogroup changes in IMD were analyzed. A total of 14 studies were included according to PRISMA guidelines. In China, from 2010 to 2020, the highest proportion of Nm in IMD was NmC, with 49.7% (95% CI: 35.8%-63.5%), followed by NmB with 30.2% (95%CI:17.3%-43.0%) and NmW with 23.8% (95%CI: 7.0-40.7%). Before 2014, NmC was the major circulating serogroup, with 59.6% (95% CI: 43.8%-75.4%), followed by NmW with 24.4% (95% CI: 5.9%-42.9%). After 2015, IMD cases caused by NmB were increasing, the proportion of NmB reached to 52.4% (95% CI: 31.8%-73.1%). The age groups of children from 0 to 5 years and from 6 to 10 years represented, respectively, 29.6% (95% CI: 16.8%-42.4%) and 28.9% (95% CI: 12.1%-45.8%) of all IMD cases were reported. In China, NmB, NmC and NmW were the major serogroups causing IMD between 2010 and 2020. Since 2015, the proportion of NmB increased rapidly. The current serogroup distribution in China highlights the need of replacing the meningococcal polysaccharide vaccines that are being used in the National Immunization Program with more appropriate vaccines.