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Vaccines for adults and why you should get them

An adult getting a vaccine shot

Are you up to date on all the vaccines you need? There’s a 4 in 5 chance you’re not. An Optum expert explains why shots are so important and the ones to consider.

When you visit a doctor with a child, you expect vaccines to be on the list of talking points. But when you’re an adult, they can slip through the radar. In fact, an estimated 4 in 5 adults aren’t up to date on their shots.1 And this could put you and your community at serious risk.

Staying on top of important vaccines should be a no-brainer. But many adults hesitate to get the regular vaccinations they need, says Andrew Cougill, MD. He’s a family practice doctor for American Health Network, part of Optum, in Indianapolis. “Many people dislike shots for a variety of reasons,” he says.

For some, work and life get in the way. Others don’t fully understand what vaccines do. Or they fear that shots may cause harm. (If cost is a barrier, Optum Perks can help you save. Download free coupons now.)

Here, we answer your top questions about vaccines in adulthood. Plus, learn the specific shots you may want to talk about with your doctor.

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I had vaccines when I was a kid. Why do I need more now?

Vaccines can wear off over time.2 As we age, our bodies need help fighting different diseases than when we were young. So you may need a vaccine that you didn’t get as a child.

Viruses are germs that can cause illnesses. And some viruses have different strains. The viruses that cause the flu and COVID-19 are perfect examples. (Remember the omicron and delta variants of the coronavirus?) “A virus’s genetics can change,” says Dr. Cougill. “This allows them to avoid our immune system longer.”

Vaccines are made to fight specific strains of a virus. But if those strains change, you may need an updated vaccine to help keep you safe, adds Dr. Cougill.

Is natural immunity better than the kind we get from vaccines?

Both can train your immune system to fight off diseases for a long time, says Dr. Cougill. But there are many reasons for not relying on natural immunity alone.

Natural immunity is the protection your own immune system makes against a germ. The catch? You first have to get sick. And that can be risky. Sometimes these diseases can lead to serious issues. In the worse cases, they can even cause death. For example, chickenpox can cause pneumonia. (Pneumonia is a lung infection.) And hepatitis B can raise your chances for having liver cancer, says Dr. Cougill. (Hepatitis B is a liver infection.) So why not stop yourself from getting sick in the first place?

Another key difference is how well you’re protected. Vaccines, such as the one for COVID-19, provide stronger protection than your natural immune response. That protection also lasts longer.6

Can herd immunity protect me instead?

Not always. Herd immunity means that a lot of people in a community are immune to a disease, so it hardly ever spreads from person to person.3 Even those who aren’t vaccinated (or have natural immunity) are protected.

But it’s hard to know how many people need to be immune for this to happen, says Dr. Cougill. (It usually depends on how easily a disease spreads.) It’s never a sure thing.

This also depends on how many folks in your area have chosen not to be vaccinated. Outbreaks can happen if not enough people are immune to a disease. For example, measles was thought to be gone in 2000. But several people became sick with it in the U.S. in 2019. The cause? Too few people had the measles vaccine.4

What are the vaccines I need as an adult?

The best person to answer that is your doctor. You may have missed vaccines as a child. So they’ll make sure you’re up to date on the shots you need. Those might include:

  • Chickenpox
  • Human papillomavirus
  • Hepatitis

And if you’ve had a bad reaction in the past, they can help you navigate that as well.

That said, the Centers for Disease Control and Prevention (CDC) suggests several vaccines.5 Some, such as the flu shot, you need every year. Others are just one-and-done.

The flu shot

What it is: This vaccine protects you against the flu and its effects. Some people may think the flu is no more harmful than the common cold. But the symptoms are usually more intense. You can have a fever, painful body aches and lots of congestion. The flu can bring on other illnesses. For example, a sinus or ear infection, or a lung infection like pneumonia. It can also lead to serious issues with the heart muscle or brain.7

When you need it: Pretty much everyone should get a flu shot each year. In general, the flu shot for the coming season is available in August. But if you wait a little longer to get it, that’s OK. “The timing of the influenza vaccine isn’t as vital as once thought,” says Dr. Cougill. “So anytime after August is fine,” he adds.

Tdap vaccine

What it is: This one shot protects you from three types of bacteria (germs) that can cause dangerous diseases. They are tetanus, diphtheria and pertussis.

You can get tetanus through cuts or wounds. It causes painful stiffening of the muscles.

The last two spread from person to person. Diphtheria can lead to breathing and heart issues, or even death.

You may know pertussis by its other name, “whooping cough.” It can cause violent coughing fits that make it hard to breathe or eat. Babies can’t get the pertussis vaccine until they’re 2 months old. So they’re especially vulnerable, says Dr. Cougill.

When you need it: If you never had a Tdap shot as a child, now’s the time. Talk to your doctor about getting one. Then you’ll need a booster shot every 10 years.

Pneumonia (pneumococcal) vaccine

What it is: This vaccine protects against pneumococcal disease. This disease can cause a slew of issues. The most common one is pneumonia. But it can also lead to meningitis, sepsis (or blood infections) and ear infections.

When you need it: You may need only one shot when you turn 65, depending on your vaccination history. People 65 and older are at a higher risk of serious illness from pneumococcal disease. If you’re under 65 and have a chronic disease, your doctor may recommend that you get the vaccine now.

Shingles vaccine

What it is: It protects you against the varicella-zoster virus. That’s the same virus that causes chickenpox. Here’s what happens: After a chickenpox infection heals, the virus remains quiet inside the body. Later on in life, it can reactivate and cause shingles.

This time the virus can cause a painful skin rash, usually on one side of the face or body. Some people also get blisters, numbness and shooting pains.7

When you need it: When you’re 50 or older. As you age, the risk of shingles increases. While a chickenpox vaccine came about in 1995, most people are living with the virus that causes shingles.

COVID-19 vaccine

What it is: We’ve heard a lot about this vaccine during the pandemic. It helps prevent you from becoming seriously ill from COVID-19.

When you need it: If you haven’t had your first two doses, it’s not too late. And if it’s been a while since you've had your first doses, you may consider a COVID-19 booster shot. Protection may wane after four to six months, says Dr. Cougill. So continued boosters may be required.

Getting vaccinated when it’s time is a smart way to keep yourself healthy and safe. What's recommended for you will depend on your age, where you live, community outbreaks and your future travel plans, says Dr. Cougill. “It’s best to ask your doctor what’s right for you,” he adds.



  1. Immunization Action Coalition. Adult immunization: Importance of staying up to date with vaccines. Accessed June 16, 2022.
  2. Centers for Disease Control and Prevention. There are vaccines you need as an adult. Updated July 30, 2021. Accessed June 16, 2022.
  3. Centers for Disease Control and Prevention. Vaccine glossary of terms. Updated July 30, 2020. Accessed June 16, 2022.
  4. Centers for Disease Control and Prevention. Measles elimination. Updated November 5, 2020. Accessed June 16, 2022.
  5. Centers for Disease Control and Prevention. What vaccines are recommended for you. Updated March 30, 2022. Accessed June 16, 2022.
  6. Morbidity and Mortality Weekly Report. Reduced Risk of Reinfection with SARS-CoV-2 After COVID-19 Vaccination — Kentucky, May–June 2021. Last reviewed August 12, 2021. Accessed July 7, 2022.
  7. Centers for Disease Control and Prevention. Flu symptoms & complications. Last reviewed September 21, 2021.
  8. Centers for Disease Control and Prevention. Shingles vaccination. Last reviewed May 24, 2022. Accessed July 7, 2021.

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