Viruses

Several viruses including varicella-zoster, herpes simplex, and Epstein-Barr (EBV) may cause facial paralysis.

The varicella-zoster virus causes Ramsay-Hunt syndrome, in which patients often have a history of ear pain, peripheral facial paralysis, and a rash located in the ear canal. Ramsay-Hunt syndrome is also characterized by hearing loss, painful sensitivity to noise, and reduced tearing. Full recovery is usually less common than in Bell’s palsy, and more patients end up with complete nerve loss and synkinesis.

Ear infections, infectious mononucleosis, and AIDS may also cause facial paralysis.

Lyme Disease

Another known infectious cause for facial paralysis is Lyme disease, seen more in the East Coast and caused by a tick commonly found on deer. Approximately 11 percent of patients suffering from Lyme disease develop facial paralysis. Paralysis is on both sides of the face in 30 percent of cases.