Abstract:
Objective To analyze the epidemiological and etiological characteristics of a case of epidemic cerebrospinal meningitis caused by Neisseria meningitidis (Nm) serogroup B infection in a maternity center in Zhangjiakou city, Hebei province in 2024.
Methods An epidemiological investigation was carried out for the case, and samples of the case and close contacts were collected for isolation and culture. The isolates were subjected to strain identification, serogroup identification, and antimicrobial susceptibility testing. Molecular typing, average nucleotide consistency (ANI) analysis, and single nucleotide polymorphism (SNP) analysis were performed with 13 Nm serogroup B strains (including cases, close contacts, and healthy people) collected in Hebei province, 2024.
Results Both the isolates from the case in Zhangjiakou and the isolates from close contacts were Nm strains of the B serogroup. The results of antimicrobial susceptibility testing showed that the isolate from the case (HE2024ZJK001) and one close contact (HE2024ZJK002) were sensitive to cefotaxime, ceftriaxone, meropenem, azithromycin, minocycline, chloramphenicol, and rifampin, while they were not sensitive to ciprofloxacin, levofloxacin, compound sulfamethoxazole, ampicillin, or penicillin. Both HE2024ZJK001 and HE2024ZJK002 belonged to a new sequence type (ST) ST-18512 and the same clonal complex (CC) CC4821. In addition, the two strains showed the ProA typing results of P1.20, 23, H factor-binding protein of variant 2 (v2), the sub-variant of v2.16, and the NHBA amino acid type of Peptide 669, and neither carried the NadA gene. The results of phylogenetic analyses based on ANI and SNP showed that the Zhangjiakou isolates (HE2024ZJK001 and HE2024ZJK002) had the same source and were most closely related to the Shijiazhuang isolate in Hebei province (HE12NME031) and the Guangdong isolate (Nm441107).
Conclusions This case has been the first epidemic cerebrospinal meningitis case in Zhangjiakou since 2011, and it occurs in a place where mothers and infants are crowded. The results suggest that in the future, the health monitoring, especially epidemic cerebrospinal meningitis monitoring, should be strengthened for special groups of infants and young children to prevent local outbreaks.