Prevalence of herpesviruses in cranial nerve ganglia

A number of cranial nerve disorders are known to result from viral infectio n or reactivation, including Bell's palsy, Ramsay Hunt syndrome and herpeti c laryngitis. The consequences of these diseases are well established altho ugh the patient population at risk is not. Prevalence studies in the genera l population are an initial step toward defining individuals at risk. The a im of this study was to determine the prevalence of herpesvirus DNA in cran ial nerve ganglia in a random population sample. Qualitative molecular biol ogic analysis using polymerase chain reaction assay of the trigeminal, geni culate, vestibular, spiral and vagal ganglia was used in 18 randomly select ed fresh cadaver heads. Herpes simplex virus (HSV) DNA was detected in 42% of all ganglia surveyed. Varicella zoster virus (VZV) DNA was detected in 4 4% of all ganglia. The difference in the prevalence rate between viruses wa s not significant (p = 0.63). At least 1 of the 2 viruses was found in 65% of all ganglia. Both HSV and VZV can commonly be recovered from cranial ner ve ganglia. In order to confirm a viral etiology for various cranial nerve disorders. demonstration of a significant difference in prevalence of the v iruses in specimens from afflicted individuals will be necessary.