Detection of the serogoups and serotypes causing bacterial meningitidis in Bangui, 2012

The aim of this study was to identify the serogroup and serotypes causing bacterial meningitidis and to determine their prevalence in Bangui, Central African Republic.

Cerebrospinal fluid (CSF) from patients with suspected meningitis were collected and tested with cell counts, Gram staining, cultures, the latex agglutination test (LAT), and real-time PCR that used specific primers and probes for S. pneumoniae, N. meningitidis, and H. influenzae. Patients were eligible if they had a CSF sample as well as information about cell counts, Gram staining, the culture, the LAT, and the PCR. Antibiotic detection disks from Bio-Rad laboratory were used to test for the presence of antibiotic activity in the CSF. An uncorrected Chi² test was used for comparisons.

Of the 216 CSF samples collected, 71 were analyzed: 17 Gram stains were positive, as were 6 cultures, 15 LATs, and 33 PCRs. Among the latter, the serogroup distribution was highest for S. pneumoniae, which accounted for 82% (27/33) of the positive cases; H. influenzae type b accounted for 12% (4/33), and N. meningitidis A for 6% (2/33) positive cases. N. meningitidis No W₁₃₅, N. meningitides B, N. meningitides X, or Streptococcus C serogroups were isolated.

One year after the introduction of the PCV 13 vaccine, S. pneumoniae was identified as the predominant disease-causing strain. This study demonstrated the essential role of laboratory confirmation of meningitis cases to assess changes in disease epidemiology.