Chickenpox, once contracted, produces permanent immunity, but years later it can be followed by shingles . The Varicella zoster virus (VZV), in fact, has the ability to remain latent in the spinal nerve ganglia, invaded during the primary infection, without giving symptoms and, in 10-20% of cases, it can be reactivated, causing the so-called " fire of St. Anthony "(Herpes zoster).
The subject, therefore, will not recur the chicken pox, but a local cutaneous manifestation characterized by clusters of vesicles that cause a burning pain along the course of the nerve, where the virus is stationed. The events triggering the reactivation are not clear, but it is known that the phenomenon is more frequent with age and in patients with deficiencies in the immune system.
A person suffering from shingles can transmit chickenpox (but not shingles) to another person who has never contracted it (or who has not been vaccinated). For contagion to occur, however, direct contact with the vesicular lesions (in which the varicella virus is present) is necessary. In fact, during the St. Anthony's fire, the viral agent does not usually affect the lungs and cannot spread by air (unlike what happens during chickenpox).
