Clinical and epidemiological characteristics of the 2023 enterovirus meningitis outbreak: regional hospital experience

Objective. To conduct a comprehensive analysis of clinical and epidemiological features, laboratory characteristics, and the effectiveness of organizational decisions during a large-scale outbreak of aseptic meningitis in 2023.

Materials and methods. A retrospective analysis of 880 cases of meningitis hospitalized in a regional infectious disease hospital during the epidemic rise was performed. The study cohort included 754 children (85.7%) and 126 adults (14.3%). Etiology verification was performed by PCR. Cerebrospinal fluid (CSF) parameters, duration of hospitalization, and outcomes were evaluated.

Results. The outbreak was characterized by an “explosive” increase in incidence caused by the combined circulation of Coxsackie A6 and ECHO 30 enteroviruses (82.2% of verified cases). It was found that in 24% of cases in children, neutrophilic pleocytosis was recorded at the onset of the disease, mimicking the bacterial nature of inflammation. This required a revision of diagnostic algorithms with the introduction of repeated lumbar punctures to monitor sanitation. Adult patients were characterized by a longer hospital stay (17–19 days versus 13–14 in children) and required antibiotics 2.5 times more often. The use of tactics of early discharge of patients with residual pleocytosis (<30 cells/µl) allowed coping with the peak load. Mortality in the study group was 0%.

Conclusion. Neutrophilic pleocytosis is a frequent variant of the onset of enteroviral meningitis (CVA6/ECHO30), which requires alertness in differential diagnosis. The introduction of dynamic cerebrospinal fluid monitoring allows minimizing antibacterial therapy safely and optimizing bed turnover.

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