Calming your concerns: how on-time vaccinations protect your child

Dr. Kisha Davis is a family physician, public health leader, and mom of three who knows firsthand what it’s like to sit on both sides of the exam room. As a physician, she’s delivered babies and supported families through everything from first fevers to college sendoffs. As a mother, she’s held her own babies while they got their shots. Dr. Davis also serves on the Board of Directors for the American Academy of Family Physicians. In this interview, she answers the most common questions parents ask about vaccines, how they work, why timing matters, and what to know before your next well-child visit.

Motherly: Let’s start with the basics. What is a vaccine, and how does it actually work?

Dr. Kisha Davis: A vaccine is a weakened or inactive version of an infection that helps your immune system recognize it without causing full-blown illness. When your body sees that infection again, it knows how to respond quickly, which means you’re much less likely to get seriously sick. Vaccines help you build immunity in a safe and controlled way.

Parents often encounter vaccines for the first time during well-baby visits. Why is it important to follow the childhood vaccination schedule?

The vaccination schedule is based on science. It reflects when children are most at risk for specific illnesses and when their immune systems are best able to respond. For example, the MMR vaccine works best when given around 12 months of age, while the hepatitis B vaccine can be given right after birth. Other vaccines, like meningitis, are most effective when given later in childhood. The timing isn’t random, it’s researched and evidence-based. Plus, some vaccines work better together, which is why doctors often give them in combination. Fewer needle sticks, fewer visits, and stronger protection.

Some parents wonder if it’s safer to delay vaccines or space them out. What are the risks?

Delaying vaccines can leave your child vulnerable when they’re most at risk. For instance, measles in a toddler is much more dangerous than in an older child. And delaying vaccines often means more appointments, more needle sticks, and more stress for the child and the parent. From a public health perspective, skipping or spacing vaccines also increases the chance of disease outbreaks.

You mentioned measles. Why are we hearing about it again, even though there’s a vaccine?

Vaccines have worked so well that many people today have never seen these illnesses. I’ve never seen a case of measles in my medical career, and I’ve only seen chickenpox in my childhood friends. But diseases like measles are still out there. Because of vaccine hesitancy, we’ve seen outbreaks return. Measles, once nearly eliminated in the U.S., is now reemerging in communities with low vaccination rates. These are preventable diseases, and it’s heartbreaking to see them make a comeback.

What do you want parents to understand about the real-world impact of vaccines?

Vaccines have saved millions of lives. In the early 1900s, 1 in 16 children died before their first birthday. Today, that number is fewer than 1 in 179. My own grandmother lost a sibling to meningitis and had another almost die from whooping cough. We don’t hear stories like that anymore because of vaccines. And while people often say “Well, I had chickenpox or measles and I was fine,” they’re forgetting the people who didn’t survive or who live with long-term complications. Polio survivors are still among us. We can’t forget that history.

What kind of side effects should parents expect after vaccines, and when should they be concerned?

Most common side effects are mild, soreness at the injection site, crankiness, low-grade fever, or changes in appetite. These typically go away in a day or two. More serious symptoms, like a persistent high fever or refusal to eat for several days, warrant a call to your doctor. Also, if a child gets sick shortly after a vaccine, it’s often because they were exposed beforehand. Vaccines take a couple of weeks to be fully effective, so that timing can be confusing.

Some parents worry about “too many shots, too soon.” How does a baby’s immune system handle vaccines?

Babies are exposed to antigens, the things that trigger an immune response, all the time. They’re crawling on the floor, grabbing the dog’s tail, putting everything in their mouths. Their immune systems are built to handle that. Thirty years ago, vaccines exposed babies to about 3,000 antigens. Today, it’s fewer than 300, and we protect against more diseases. Vaccines are carefully designed to work with the immune system, not overwhelm it.

We still hear about autism and vaccines. Can you clarify what the science says?

The claim that vaccines cause autism has been thoroughly debunked. The original study that raised that concern was retracted, and numerous large-scale studies have shown no link between vaccines and autism. What we know now is that autism likely has a genetic basis, and symptoms often emerge around the same time kids receive the MMR vaccine, leading some parents to falsely assume a connection. But science has made it very clear: vaccines do not cause autism.

What’s your take on natural immunity—just letting kids get the illness?

Some illnesses are mild, but many are not. Meningitis, pertussis, measles, chickenpox—these can cause severe complications, hospitalization, even death. With vaccines, you get immunity without the suffering. Plus, vaccines can be updated as diseases evolve, like we’ve seen with COVID and flu. You don’t need to get sick to get protected.

What about vaccine safety? How do we know they’re safe for kids?

Vaccines go through rigorous testing, first in labs and on animals, then in multiple phases of human trials. Even after approval, they’re continuously monitored. Some vaccines, like the pneumococcal vaccine, have been updated over time to improve safety and effectiveness. Safety isn’t a one-time check; it’s ongoing.

How can parents tell if vaccine information online is trustworthy?

Look for information from .gov websites like the CDC or reputable medical organizations like the American Academy of Family Physicians or the American Academy of Pediatrics. These sources are backed by science and reviewed by experts. If you’re on a parenting site or social media, check to see where their information is coming from. Are they citing real sources? If not, be cautious.

Can you explain how vaccines help protect the entire community, not just the individual child?

This is where herd immunity comes in. Some people can’t be vaccinated—newborns, cancer patients, people with certain allergies. When the majority of the community is vaccinated, the disease has nowhere to spread. I remember when my son was born in October. He was too young for the flu shot, so I asked everyone who wanted to visit to get vaccinated. That’s how you protect the most vulnerable, by   sure those around them are immune.

Are there vaccines kids need before heading off to college?

Yes—meningitis is a big one. We often hear tragic stories of young adults getting seriously ill during their first year away. It’s heartbreaking because it’s preventable. The tetanus booster and HPV vaccine are also important. The HPV vaccine prevents several types of cancer and is recommended for both boys and girls. You can start as early as age 9, and it’s best to finish before they go to college.

If a parent is nervous about asking vaccine questions at the doctor’s office, what’s your advice?

Come prepared. Write your questions down ahead of time. If your practice has a patient portal, send the questions in advance. Don’t wait until the last minute of the visit. Start by saying, “I want to do what’s best for my child, and I have some concerns I’d love to talk through.” You deserve clear answers and a respectful conversation.

Where can parents find science-backed vaccine resources you trust?

Start with familydoctor.org, which is run by the American Academy of Family Physicians. The American Academy of Pediatrics and the CDC also have excellent, reliable information. Those are the places I send my patients when they have questions.