AUTHOR=Gofrit Shany Guly , Pikkel Yoav Yechezkel , Levine Hagai , Fraifeld Shifra , Kahana Merhavi Shlomzion , Friedensohn Limor , Eliahou Ruth , Ben-Hur Tamir , Honig Asaf 

TITLE=Characterization of Meningitis and Meningoencephalitis in the Israeli Defense Forces From 2004 to 2015: A Population-Based Study

JOURNAL=Frontiers in Neurology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2022.887677

DOI=10.3389/fneur.2022.887677

ISSN=1664-2295

ABSTRACT=Background: Meningitis and meningoencephalitis (MME) are potential medical emergencies. Mandatory reporting of all MME cases in the Israel Defense Force (IDF) allows accurate characterization of MME incidence and course. In the present study we describe the epidemiology of MME in soldiers.
Methods: Medical charts of 860,000 combat and noncombat soldiers serving during the years 2004−2015, accounting for 2,256,060 patient years, were retrospectively evaluated. The diagnosis of MME was based on signs of meningeal irritation and counts of >5 white blood cells (WBC) in the cerebrospinal fluid (CSF). Data on the diagnosis of bacterial or aseptic MME, significant sequelae, and associated mortality were collected. 
Results: 273 cases of MME were diagnosed. Overall MME incidence was 12.1/100,000 patient-years. Bacterial and viral pathogens were identified in 31/273 (11.4%) and 52/273 (19.0%) cases, respectively. Combat soldiers had higher incidence of bacterial meningitis (14/40 (35.0%) vs. 31/212 (14.6%); p=0.002) and meningoencephalitis (13/40 (32.5%) vs. 33/212 (15.6%); p=0.023) compared to noncombat soldiers. Their clinical presentation was more severe, including confusion (10/40 (25%) vs. 22/212 (10.4%); p=0.018), focal neurological deficits (12/40 (30%) vs. 11/212 (5.2%); p<0.0001), and status epilepticus (3/40 (7.5%) vs. 0/212 (0.0%); p<0.01). Mortality among combat soldiers was higher (5/40 (15%) vs. 1/212 (0.5%); p<0.001). N. meningitidis was the most frequently isolated bacteria, despite universal preventative vaccination. 
Conclusions: The incidence of bacterial MME in the IDF is higher than in the civilian population. Combat soldiers presented with higher incidence of meningoencephalitis and bacterial meningitis.