Direct molecular testing to assess the incidence of meningococcal and other bacterial causes of meningitis among persons reported with unspecified bacterial meningitis

• We examined Neisseria meningitidis (Nm) surveillance among culture-negative cases.
• We ran nucleic acid tests (NAT) on 138 CSF samples from Nm culture-negative reports.
• NAT results on specimens were concordant with hospital microbiology findings in 80%.
• No additional Nm cases were found, but other pathogenic organisms were identified.
• Our surveillance system appears to be effective at capturing cases of Nm meningitis.

Confirmed and probable cases of invasive Neisseria meningitidis (Nm) infection are reportable in New York City. We conducted a study to identify Nm among culture-negative reports of bacterial and viral meningitis. During the study period, 262 reports of suspected meningitis were eligible. Cerebrospinal fluid (CSF) specimens from 138 patients were obtained for testing. No Nm cases were detected. Results from real-time polymerase chain reaction and 16S on CSF specimens were concordant with hospital microbiology findings in 80%; however, other pathogenic organisms were detected in 14 culture-negative specimens. New York City's surveillance system appears to be effective at capturing cases of Nm meningitis. Nucleic acid testing is useful for detecting the presence of bacterial DNA when antibiotic therapy precedes lumbar puncture or bacterial cultures are negative. It remains unanswered whether culture-negative cases of Nm bacteremia are being missed by reportable disease surveillance.