Reactivation of latent varicella-zoster virus most commonly manifests as which condition?

• A. Chickenpox
• B. Mononucleosis
• C. Shingles
• D. Rubella

Answer: (C)

Latent varicella-zoster virus remains dormant in dorsal root ganglia after the initial chickenpox infection and can reactivate later in life. When it reactivates, it travels along sensory nerves to the skin, producing herpes zoster, or shingles. The key clinical feature is a painful, unilateral vesicular rash that follows a dermatomal distribution, often with itching or burning before the rash appears. This pattern—localized, nerve-root–distributed pain with a vesicular eruption—distinguishes shingles from the primary varicella infection (chickenpox), rubella, or mononucleosis, whose typical presentations are different. Recognizing this reactivation is important because it carries a risk of postherpetic neuralgia, especially in older adults.