Herpes simplex virus infection in Bulgarian patients with neurological diseases

•High positivity of HSV-1 (16.5%) and HSV-2 (6.2%) in CSF of neurological patients.•HSV-1 is with predominant role in development of both encephalitis and meningitis.•HSV-2 is not with predominant role for development of meningitis.•No significant difference of HSV prevalence in CSF according to gender and age.•HSV is a frequent causative agent of neurological diseases in Bulgaria.