As I turned 50, I found myself in the clinic not as a doctor, but as a patient. The nurse swabbed my arm, counted down softly — “One, two, three” — and in went the zoster vaccine. 

Sometime later, my arm throbbed with that familiar post-injection ache, the kind that says your immune system is awake and doing its job. I rubbed the spot, grabbed an ice pack and thought, “So this is 50.”

When we think of vaccines, we often picture babies in diapers getting their first series of shots. But the truth is, immunity isn’t a one-time deal — it’s a lifelong partnership. As we age, our defenses wane, diseases evolve and our risk factors change. The zoster vaccine, which protects against shingles, is one of those important adult milestones — a quiet but powerful reminder that prevention doesn’t stop at childhood.

This is the essence of the life-course approach to immunization — the understanding that protection should follow us through every stage of life. Our risks shift as we grow older: young adults encounter different exposures, mid-life brings chronic conditions and older age increases vulnerability to infections like pneumonia and shingles. A life-course approach makes sure vaccination schedules adapt to our age, lifestyle and specific health risks, reminding us that staying protected is not a childhood chapter but a lifelong commitment

Shingles, or herpes zoster, is caused by the reactivation of the same virus that causes chickenpox. After decades of lying dormant in nerve cells, it can awaken when immunity dips, causing painful rashes and, in some cases, lingering nerve pain known as post-herpetic neuralgia. The recombinant zoster vaccine (RZV) is now recommended for adults 50 years and older — two doses given two to six months apart. Even those who’ve had shingles before, or who received the older live vaccine, are advised to get it because RZV provides stronger and longer-lasting protection.

That single jab made me realize how many adults still put off their own vaccinations, either because they think they’re “too old for shots” or because they simply lose track of what’s due. But vaccines aren’t just about avoiding infection — they’re about preserving function, preventing hospitalization and maintaining quality of life.

What else should be on an adult’s vaccination checklist?

For starters, the influenza vaccine remains a yearly must. Influenza is far from “just the flu” — it can lead to severe illness, especially among older adults and those with chronic conditions like diabetes or heart disease. Each year’s formulation targets the strains expected to circulate that season, so annual protection matters.

Then there’s the Tdap booster, which guards against tetanus, diphtheria and pertussis (whooping cough). Adults should receive one dose of Tdap if they never had it as a teen, followed by a booster every 10 years — either Td or Tdap. Pregnant women are advised to get Tdap during each pregnancy to protect their newborns from pertussis in the first vulnerable months of life.