Varicella zoster virus shingles or herpes zoster. VZV can also infect the central nervous system, with a 2013 article reporting an incidence rate of 1.02 cases per 100,000 inhabitants in Switzerland, and an annual incidence rate of 1.8 cases per 100,000 inhabitants in Sweden. Other serious complications of varicella zoster infection include postherpetic neuralgia, Mollaret's meningitis, zoster multiplex, and inflammation of arteries in the brain leading to stroke, myelitis, herpes ophthalmicus, or zoster sine herpete. In Ramsay Hunt syndrome, VZV affects the geniculate ganglion giving lesions that follow specific branches of the facial nerve. Symptoms may include painful blisters on the tongue and
Contagious disease illustrated classically by tuberculosis, which is clearly transmissible from person to person, but was not classically considered a contagious disease. In the present day, most sexually transmitted diseases are considered contagious, but only some of them are subject to medical isolation. Originally, the term referred to a "contagion" (a derivative of 'contact') or disease transmissible only by direct physical contact. In the modern day, the term has sometimes been broadened to encompass "any" communicable or infectious disease. Often the word can only be understood in context, where it is used to emphasise very infectious, easily transmitted, or especially severe communicable