UKMLA PLAB AMC USMLE Prometric MCQ

Correct Answer: E

Explanation:
the varicella virus is reactivated after being latent in the dorsal root ganglian Shingles occurs becuase the varicella virus, the cause of both chickenpox and herpes zoster (shingles), is reactivated after being latent in the dorsal root ganglia. Immunoglobulins directed againsts viral antigens (choice a) is thought to be the pathogenesis of multiple sclerosis, not herpes zoster.The variola virus (choice b) is responsible for smallpox, not chickenpox and herpes zoster.Choice c is not correct because often herpes zoster occurs when there is a decrease in the activity of the immune system, such as occurs with aging or immunosuppresent drugs.  The varicella virus is latent in the dorsal root ganglion, not the ventral root ganglia; therefore choice (d) is incorrect.