π‘οΈ Vaccine Immunity Duration Guide
How long each vaccine's protection typically lasts.
Estimated protection window
For informational purposes only, not medical advice.
Protection duration varies enormously by vaccine: MMR and polio protect for life after the full series, tetanus needs a booster every 10 years, flu needs a new shot each season, and COVID protection wanes over months. A Tdap dose from 2018 is due for a booster around 2028. This guide gives the typical duration for each common vaccine plus a booster estimate from your last dose date.
Duration depends on the pathogen and the vaccine type. Stable viruses with lifelong immunity after natural infection (measles) make lifelong vaccines; fast-mutating ones (flu) or waning responses (pertussis) need repeats.
How to Use This Guide
Select the vaccine and enter the year of your last dose. The tool shows the typical protection duration and when a booster is roughly due.
Choose the vaccine from the list.
Enter the year of your most recent dose.
Read the typical duration and booster estimate, then confirm with your doctor or pharmacist.
Typical Durations
| Vaccine | Typical protection |
|---|---|
| MMR, Polio | Lifelong after complete childhood series. |
| Tdap / Td | About 10 years; booster each decade. |
| Hepatitis B, HPV, Varicella | Long-term, likely decades to lifelong. |
| Shingles (Shingrix) | Many years; follow age-based guidance. |
| Influenza | One season; reformulated yearly for new strains. |
| COVID-19 | Wanes over months; updated guidance yearly. |
These are population-typical ranges, not guarantees: individual responses vary, and guidance updates as evidence accumulates. Tetanus is the one to calendarize because its 10-year rhythm is easy to forget and the disease is unforgiving.
Worked Example
Last Tdap in 2018: add the 10-year duration to get a booster estimate around 2028. A single Tdap as an adult followed by Td boosters each decade is the standard rhythm, with Tdap preferred once in adulthood and during each pregnancy.
Flu example: vaccinated October 2025, protection covers the 2025-26 season and then it is done; next season needs the reformulated shot regardless. COVID follows a similar seasonal-guidance pattern in current CDC recommendations.
Reading Your Result
Treat lifelong entries as durable but not magical: immunocompromised people may need different schedules. Treat the 10-year tetanus entry as a real deadline worth calendaring. Treat flu and COVID entries as seasonal chores tied to current guidance, which changes.
My take: the highest-value action on this page is checking your tetanus date. It is the most commonly lapsed adult vaccine, the booster is trivial, and stepping on a nail should not be a gamble.
Limits
Durations are approximate educational ranges; real schedules depend on age, health conditions, occupation, travel, and evolving CDC guidance. Immunocompromised patients follow different rules entirely. Your immunization record plus your clinician beats any estimate here.
Related Tools
Understand trial numbers with the vaccine efficacy calculator and check the adult schedule in our US vaccine schedule checker.
For informational purposes only, not medical advice. Consult a healthcare professional.
Frequently Asked Questions
How long does vaccine immunity last?
It varies: MMR and polio are lifelong after the full series, tetanus about 10 years, hepatitis B and HPV decades, flu one season, COVID months. This page gives typical durations per vaccine.
How often do you need a tetanus booster?
Every 10 years (Td or Tdap), with Tdap preferred at least once in adulthood and during each pregnancy. Dirty wounds may need one sooner if it has been over 5 years.
Do I need a flu shot every year?
Yes. Protection wanes and the strains change, so the vaccine is reformulated annually. Last year's shot does not cover this year's season.
How long does the COVID vaccine last?
Protection against infection wanes over months; protection against severe disease lasts longer. Current CDC guidance is updated periodically; follow the latest recommendation for your age and risk.
Is MMR really lifelong?
For most people, yes: two doses in childhood provide decades-long, effectively lifelong protection against measles, mumps, and rubella. Certain exposures or outbreaks can prompt an extra dose per public health guidance.
How long does hepatitis B vaccine last?
Long-term, likely lifelong for those who responded to the series. Routine boosters are not recommended for the general population; healthcare workers follow exposure protocols.
Do adults need HPV vaccine?
It is routinely recommended through age 26 and up to 45 based on shared decision-making. Protection after the series appears long-lasting in studies so far.
How long does shingles vaccine protection last?
Shingrix shows strong protection for many years in studies; current guidance is the two-dose series at 50+ without a defined routine booster yet.
Can immunity be checked with a blood test?
For some diseases (hepatitis B, measles, varicella), antibody titers can confirm immunity, used in healthcare and after exposures. For most vaccines, following the schedule beats testing.
Where is my immunization record?
State immunization registries, your doctor's office, pharmacy records, and childhood pediatrician files. Adults should keep a personal copy; this page's estimates are no substitute for the record.