United States
Ramsay Hunt syndrome is a rare complication of latent VZV infection.[4] As stated above, Ramsay Hunt syndrome might occur in the absence of cutaneous rash (zoster sine herpete). Interestingly, VZV has been detected by polymerase chain reaction (PCR) in the tear fluid of patients diagnosed with Bell palsy.[5] Ramsay Hunt syndrome is estimated to account for 16% of all causes of unilateral facial palsies in children, and 18% of facial palsies in adults. Ramsay Hunt syndrome is rare in children younger than 6 years.[4]
Ramsay Hunt syndrome is thought to be the cause of as many as 20% of clinically diagnosed cases of Bell palsy.[5]
The incidence of Ramsay Hunt syndrome among patients with HIV infection is unknown. However, it may occur at a higher rate than in the general population because individuals with HIV infection have a higher risk of VZV infection.[2]
International
Similar frequency has been reported in other countries.
Mortality/Morbidity
Ramsay Hunt syndrome is not usually associated with mortality. It is a self-limiting disease; the primary morbidity results from facial weakness. Unlike Bell palsy, this syndrome has a complete recovery rate of less than 50%.