Shingles and chickenpox are both caused by the varicella zoster virus (VZV). After recovering from chickenpox, the virus does not disappear but "sleeps" in nerve ganglia. When immunity declines due to age, illness, or immunosuppressive drugs, the virus can reactivate and cause shingles.

Upon reactivation, the virus multiplies in the ganglia and then spreads along the nerves to the skin, causing inflammation and clustered blisters. Because each nerve supplies a specific skin area, shingles typically appears as a band on one side of the body, commonly on the chest, back, abdomen, or face.

The "electric shock" sensation results from the virus inflaming and damaging nerve fibers, sending chaotic pain signals to the brain even without external stimulation. Pain can emerge before, concurrent with, or persist after the skin has healed. Shingles near the eyes, ears, or face requires early examination due to potential impacts on vision, hearing, or facial nerves.

Individuals with shingles often describe the pain as a needle prick or electric shock. *Illustration: Vecteezy*

Nerve pain is the most frequent complication of shingles. This condition is diagnosed when a patient experiences pain lasting over 90 days, causing burning, stabbing sensations, sleep disturbances, and affecting daily activities. The risk increases in older adults, those with compromised immunity, or severe rashes. Shingles can also lead to skin infections, eye damage, facial paralysis, and other neurological complications.

Individuals suspected of having shingles should seek early medical attention, especially within the initial 72 hours, to receive prescribed antiviral medication. Even if more than 72 hours have passed, but new blisters are appearing, a rash is present on the face or near the eyes, pain is severe, or underlying conditions exist, a consultation is still necessary. Keep the affected area clean and dry, wear loose clothing, and apply cool compresses gently; avoid applying leaves, pricking blisters, or using unverified topical remedies.

Vaccination reduces the risk of developing shingles and its complications. Even those who have had shingles can experience recurrence, so vaccination is still needed. The Shingrix vaccine is recommended for individuals aged 50 and older (two doses administered two months apart) and for high-risk individuals aged 18 and older (two doses administered one month apart), offering approximately 97% effectiveness in preventing the disease and reducing complications by up to 90%.

Dr. Danh Thi My Hong

Medical Manager, VNVC Vaccination System

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