Shingles vaccination – why is it important in older adults?

Have you heard of chickenpox? Many people remember having it as children. This common illness is marked by itchy, fluid-filled blisters, red rashes, and painful skin ulcers that eventually form scabs. If you were born in an era with poor hygiene, overcrowding and before the chickenpox vaccine was available, it's likely you had chickenpox, even if you don’t recall it.

Chickenpox is caused by the highly infectious Varicella-Zoster virus (VZV). You might wonder how chickenpox is connected to shingles. The connection is significant. Shingles, or Herpes Zoster, is also caused by VZV and presents as a painful rash. After recovering from chickenpox, the virus remains dormant in the body and can reactivate later, leading to shingles. Thus, anyone who has had chickenpox is at risk for shingles. Studies indicate that over 99% of adults aged 50 and older worldwide have been exposed to VZV. In India, a seroprevalence study found that more than 90% of people by age 40 carry the virus.

Unlike chickenpox, shingles is not as contagious. You cannot catch shingles from someone with the condition, but you can contract chickenpox from someone with shingles if you haven't had chickenpox or the vaccine. Chickenpox can spread through direct contact with the fluid from shingles blisters or by inhaling virus particles.

Chickenpox is more commonly seen in children, while shingles typically affects older adults. Most people experience shingles only once, though some may have it more than once. Data shows that one in three people will develop shingles in their lifetime. The rash often appears on one side of the face or body and is usually painful, itchy, or tingling. Before the rash appears, individuals may experience symptoms like fever, headaches, chills, and upset stomach apart from the pain, itch and tingling. The rash usually forms blisters that scab over within 7 to 10 days and typically clears up in 2 to 4 weeks. In rare cases, shingles can be more widespread, resembling a chickenpox rash, especially in individuals with weakened immune systems.

One of the most concerning complications of shingles is postherpetic neuralgia (PHN), which causes long-term nerve pain where the rash occurred, lasting months or even years. About 10% to 18% of shingles patients experience PHN, with older adults at a higher risk. Other complications can include vision loss, hearing loss, bacterial infections, pneumonia, and in rare cases, brain inflammation or death.

If you’ve had chickenpox, your risk of shingles—and its complications—increases with age, weakened immune systems due to disease or medicinal therapy, and certain medical conditions like diabetes, kidney disease and heart disease. Adults over 50 are particularly vulnerable, with a 30% higher risk of PHN.

If you or someone you know develops shingles, seek medical attention promptly. Fortunately, shingles can be prevented with a vaccine. The shingles vaccine, recommended by organisations like WHO and CDC, is available in India. The most common and recommended brand is Shingrix, a non-live, recombinant subunit vaccine that effectively boosts immune response.

Shingrix is administered intramuscularly in two doses, spaced 2 to 6 months apart. It offers at least 10 years of protection with over 90% efficacy against shingles. It is suitable for adults 50 and older and those with weakened immune systems. Even if you've had shingles or chickenpox before, Shingrix can help prevent future occurrences.

However, Shingrix has some contraindications. It should not be given to individuals currently experiencing shingles, those with severe allergies to its components, those with severe allergies to its first dose or pregnant individuals. Mild illnesses like a cold do not prevent vaccination, but moderate to severe illnesses should be resolved first before taking the vaccine.

Side effects from Shingrix, while generally mild and short-lived, may include soreness at the injection site, swelling, itchiness, bruise, fatigue, muscle pain, headaches, shivering, fever, stomach pain or nausea. These effects usually resolve within 2 to 3 days and are significantly less severe than shingles itself.

Vaccination against shingles is crucial for older adults, as it can prevent a painful and avoidable condition.