1. United Nations Department of Economic and Social Affairs Population Division.World population aging 2013. ST/ESA/SER.A/348.2013.
2. Sepsis and immunosenescence in the elderly patient: a review;Martin S;Front Med,2017
3. Community‐acquired meningitis in older adults: clinical features, etiology, and prognostic factors;Wang A;J of American Geriatric Soc,2014
4. Meningitis with a negative cerebrospinal fluid gram stain in adults: risk classification for an adverse clinical outcome;Khoury NT;Mayo Clinic Proceedings,2012
5. Meningitis in elderly patients;Delerme S;Eur J Emerg Med,2009