Answers to Top Questions About Kids' Vaccines

Vaccines are crucial for protecting children from serious illnesses, some of which can cause long-term complications or even be life-threatening. But as a parent, it’s natural to have questions—especially as shifting news headlines create confusion for families.

Columbia pediatrician Melissa Stockwell, MD, MPH, chief of the Division of Child and Adolescent Health at Columbia, answers some of parents’ most common questions about childhood vaccines.

Why does my child need vaccines?

Vaccines protect children from diseases that can cause serious illness, hospitalization, long-term health problems, and death.

Some diseases may seem uncommon today precisely because vaccination has been so successful at controlling them in the past. When vaccination rates decline, however, these diseases can return.

Getting your child vaccinated also helps protect other children who cannot receive certain vaccines, including some babies and people with weakened immune systems.

Are vaccines safe for my child?

Yes. Vaccines recommended for children are extensively studied for safety and effectiveness, and vaccine safety continues to be monitored after vaccines are approved.

What side effects should I expect after vaccination?

Most side effects are mild and go away quickly. Children may experience pain or swelling where the vaccine was given, fatigue, fussiness, or a low-grade fever. Serious reactions are rare.

Your pediatrician can tell you what to expect after a particular vaccine and when symptoms might warrant medical attention.

Why not just vaccinate children who are considered high risk?

For many infectious diseases, it is impossible to predict which children will be exposed, or which otherwise healthy children will become seriously ill.

People can sometimes carry and transmit infections without knowing they are infected. And diseases such as RSV can cause severe illness even in babies without known risk factors.

Routine vaccination protects children before those exposures happen.

What about vaccines for rare diseases or that may be more dangerous for certain children?

A disease does not have to be common to pose a serious risk.

Meningococcal disease, for example, is rare but can progress extraordinarily quickly and can be deadly even with treatment. A healthy adolescent can feel well one day and be critically ill the next.

Other infections can be difficult to predict based on an individual child’s apparent risk. Hepatitis B, for example, can be transmitted by someone who does not know they are infected. In children, infection can become chronic and eventually lead to cirrhosis or liver cancer.

Similarly, RSV can cause severe illness in infants who might not otherwise be considered high risk. Newer RSV prevention strategies have been shown to reduce hospitalizations among infants.

Routine immunization provides protection before an unexpected exposure occurs.

Is it safe for children to receive multiple vaccines at the same time?

Yes. Children’s immune systems are capable of responding to multiple vaccines at once.

In fact, the number of antigens (the proteins and sugars that trigger an immune response) in vaccines is small compared with what children encounter naturally.

Across routinely recommended vaccines, children are exposed to about 160 to 170 antigens. By contrast, a single bacterium can contain thousands. An ordinary bacterial infection, like an ear infection or strep throat, can therefore expose a child’s immune system to far more antigens than all doses of all recommended vaccines combined.

Combination vaccines also reduce the number of injections children need while allowing them to receive protection at the optimal time.

What about COVID-19 vaccines? Are they still available, and is my child eligible?

Yes. Right now, the vaccine is still available for children. Although the federal government no longer broadly recommends the vaccine for healthy children, the American Academy of Pediatrics(AAP), the New York State Department of Health, and others continue to recommend the COVID-19 vaccine for children who:

• Are 6 to 23 months old
• Are 2 to 18 years old and at high risk of severe COVID-19
• Have never been vaccinated
• Live in a long-term care facility or other communal setting
• Have a household contact at high risk of severe COVID-19

The AAP also recommends the vaccine for any child 2 through 18 years of age who is not included in these high-risk groups but whose caregivers desire protection against COVID-19.

While COVID-19 tends to cause milder illness in most children compared to adults, it can still lead to serious complications, including hospitalization, long COVID, or, in rare cases, multisystem inflammatory syndrome in children. Vaccination significantly reduces the risk of these complications.

Do vaccines cause autism?

No. Decades of research have found no causal relationship between vaccines and autism.

The original study that suggested a connection between the MMR vaccine and autism was retracted after serious problems with the research were identified. Numerous studies conducted since then have found no association between vaccination and autism.

Renewed public discussion about vaccines and autism does not change that scientific evidence. Pediatricians spend years training to evaluate scientific evidence, understand an individual child’s needs, and help families make informed decisions that are best for their child.

Can my child get vaccinated if they have a cold?

Usually, yes. A mild illness such as a cold or low-grade fever generally does not prevent a child from being vaccinated.

If your child has a more serious illness or high fever, talk with your pediatrician about whether vaccination should be delayed.

What if my child has an allergy or other medical condition?

True vaccine allergies are rare. Certain medical conditions, allergies, or treatments that affect the immune system may change which vaccines a child should receive or when they should receive them.

Your pediatrician can review your child’s medical history and recommend the safest and most effective vaccination plan.

Amid public confusion over vaccines, what should parents do?

Parents should talk with their child’s pediatrician rather than delay vaccination while trying to sort through conflicting information themselves. Pediatricians can explain the evidence behind vaccine recommendations, consider an individual child’s medical history, and help families decide how best to protect their child.