11/15/19

| information for health care professionals |

U.S. Department of 

Health and Human Services 

Centers for Disease 

Control and Prevention 

Reviewed January 2019

Preparing for Questions Parents May Ask about Vaccines

Many parents won’t have questions about vaccines when you 

give your strong recommendation and use language that assumes 

parents will accept vaccines for their child.

If a parent questions your recommendation, this does not 

necessarily mean they will not accept vaccines. They consider you 

their most trusted source of information when it comes to vaccines 

and sometimes parents simply want your answers to their questions. 

This sheet outlines some of the topics most parents ask about and 

tips for how to answer their questions.

Questions about the vaccine schedule and 

number of vaccines

Some parents may be concerned that there are too many vaccines 

or that their child will receive too many at one time. But, they may 

not understand that following the recommended vaccine schedule 

provides the best protection at the earliest possible time against 

serious diseases that may affect infants early in life.

Parents may ask: Can it harm my child to get several vaccines at 

one time? Does my child need all of the vaccines recommended? 

To respond, you can:

 Share that no evidence suggests that receiving several vaccines 

at one time will damage or overwhelm a healthy child’s immune 

system.

 Explain what antigens are (parts of germs) and emphasize the 

small amount of antigens in vaccines compared to the antigens 

babies encounter every day in their environment.

 Remind parents that they must start each vaccine series on time 

to protect their child as soon as possible and their child must 

complete each multi-dose series for the best protection. There 

are no data to support that spacing out vaccines offers safe or 

effective protection from these diseases.

“There’s no proven danger in getting all recommended vaccines 

today. Any time you delay a vaccine, you leave your baby 

vulnerable to disease. It’s really best to stay on schedule.”

Questions about whether vaccines are more 

dangerous for infants than the diseases they prevent

Because vaccines are very effective, many parents have not seen 

a case of a vaccine-preventable disease firsthand. Therefore, they 

may wonder if vaccines are necessary and if the risks of vaccinating 

infants outweigh the benefits of protection from vaccine preventable 

diseases.

Parents may ask: Are these diseases that dangerous? Is it likely 

that my baby will catch this disease? Will ingredients in vaccines 

hurt my baby more than possibly getting the disease could? To 

respond, you can:

 Share your experience of how these serious diseases still exist and 

explain that outbreaks still occur in the U.S. For example:

- From year to year, measles cases in the U.S. can range from 

roughly less than 100 to a couple hundred. However, in 2014, 

health departments reported cases in 667 people from 27 states.

- Between 1970-2000, health officials reported fewer than 8,000 

cases of whooping cough each year in the U.S. But since 2010, 

health officials have reported between 15,000 and 50,000 cases 

of whooping cough each year to CDC.

 Teach parents that diseases eliminated in the U.S. can infect 

unvaccinated babies if travelers bring the diseases from other 

countries. If you need up-to-date information on specific 

diseases, share Disease Fact Sheets with parents.

 Remind parents that many vaccine preventable diseases can be 

especially dangerous for young children and there’s no way to tell 

in advance if their child will get a severe or mild case. Without 

vaccines, their child is at risk for getting seriously ill and suffering 

pain, disability, and even death from diseases like measles and 

whooping cough.

“I know you didn’t get all these vaccines when you were a baby. 

Neither did I. However, we were both at risk of serious diseases 

like Hib and pneumococcal meningitis that can lead to deafness 

or brain damage. Today, we’re able to protect your baby from 

14 serious diseases before his second birthday with vaccines.”

Questions about known side effects

It is reasonable for parents to be concerned about possible reactions 

or side effects listed on Vaccine Information Statements. Vaccines, 

like any medication, can cause some side effects. Many of these 

effects are minor, treatable, and last only a few days.

Parents may ask: Will my child be okay if she has a side effect? 

I know someone whose baby had a serious reaction—will my baby 

too? To respond, you can:

 Remind parents that most side effects are mild and go away 

within a few days.

 Reassure parents that you and your staff are prepared to deal with 

serious vaccine reactions.

 Encourage parents to watch for possible side effects (fussiness, 

low-grade fever, soreness where the shot was given) and provide 

information on how they should treat them and how to contact 

you if they observe something they are concerned about.

 Share your own experience, or lack thereof, of seeing a serious 

side effect from a vaccine. Explain that serious side effects are 

very rare.

Reassure parents that the disease-prevention benefits of getting 

vaccines are much greater than the risks of possible side effects.
11/15/19

“I’ll worry if your child doesn’t get vaccines today, because the 

diseases can be very dangerous—most, including Hib, whooping 

cough, and measles, are still infecting children in the U.S. We 

can look at the Vaccine Information Statements together and talk 

about how rare serious vaccine side effects are.”

Questions about unknown serious long-term 

side effects

Parents who look for information about vaccine safety will likely 

encounter information that says vaccines can lead to serious longterm side effects. It is understandable that parents may find this 

alarming.

Parents may ask: Do vaccines cause long-term side effects? Will 

getting a vaccine permanently hurt my child’s health?

To respond, you can share that:

 Vaccines are not linked to increases in health problems such as 

autism, asthma, or auto-immune diseases.

 There is no evidence to suggest that vaccines threaten a long, 

healthy life. Conversely, we know lack of vaccination threatens 

a long and healthy life.

“We have years of experience with vaccines and no reason to 

believe that vaccines cause long-term harm. I understand your 

concern, but I truly believe that the risk of diseases is greater 

than any risks posed by vaccines. Vaccines will get your baby off 

to a great start for a long, healthy life.”

Questions about vaccine ingredients

Parents may ask about the ingredients contained in vaccines. 

Let them know that vaccines contain very small amounts of the 

ingredients listed below and that all ingredients play necessary roles 

either in making the vaccine or in ensuring that the final product is 

safe and effective.

Parents may ask: Are the ingredients in vaccines safe? 

Aren’t aluminum and mercury dangerous? 

 Preservatives prevent contamination of the vaccine. Thimerosal, 

a compound containing mercury, is a preservative only found in 

multi-dose vials of flu vaccine. 

 Adjuvants or enhancers, such as aluminum salts, are used to help 

the body develop immunity and a better immune response.

 Stabilizers, such as sugars and gelatin, are used to keep the 

vaccine potent during transportation and storage.

 Residual cell culture materials, such as egg protein, are used to 

grow enough of the virus or bacteria to make the vaccine. 

 Residual inactivating ingredients, such as formaldehyde, are used 

during the production process to kill viruses or inactivate toxins 

during the manufacturing process.

 Residual antibiotics, such as neomycin, are used during the 

vaccine manufacturing process to prevent contamination 

by bacteria.

“Each vaccine ingredient plays an important role in either making 

the vaccine or ensuring that it is safe and effective so it will 

protect your child.”

Questions about whether vaccines cause autism

Although many parents are aware that numerous studies show 

vaccines have nothing to do with autism, some parents have 

lingering questions and concerns.

Parents may ask: I’ve heard some parents say their child’s 

behavior changed after vaccines; how do you know vaccines don’t 

cause autism? Many rigorous studies show that there is no link 

between MMR vaccine or thimerosal and autism. If parents raise 

other possible hypotheses linking vaccines to autism, three items 

are key:

 Give patient and empathetic reassurance that you understand 

their infant’s health is their top priority, and it also is your 

top priority, so putting children at risk of vaccine-preventable 

diseases without scientific evidence of a link between vaccines 

and autism is a risk you are not willing to take.

 Share that the onset of autism symptoms often coincides with 

the timing of vaccines but have nothing to do with vaccines.

 Give your personal and professional opinion that vaccines are 

very safe.

“Autism is a challenge for many families and people want 

answers—including me. But well designed and conducted studies 

that I can share with you show that MMR vaccine have nothing to 

do with autism.”

Resources for questions about vaccines and autism:

 Understanding Thimerosal, Mercury, and Vaccine Safety

 Understanding MMR Vaccine Safety

Additional questions parents may ask

 Isn’t natural immunity better than the kind from vaccines?

 Do I have to vaccinate my baby on schedule if I’m breastfeeding 

him?

 Why are so many doses needed for each vaccine?

If you have additional questions from parents, reference Infant 

Immunization FAQs for regularly updated answers to common 

questions.

For information on vaccines, vaccine safety, and vaccine preventable 

diseases, visit: www.cdc.gov/vaccines/conversations