Babies & Children

Being a parent is a big responsibility with many decisions about how to best protect your children, such as how to baby-proof your house and when to switch to a booster seat. However, not all threats to your children’s safety are visible.

Vaccines help prevent infectious diseases that once killed or seriously harmed many children. Without vaccines, your children are at risk for serious illnesses including measles, mumps, whooping cough and flu, which could result in disability or even death.

Why Should I Vaccinate My Child?

Through vaccines, you have the power to protect your children from 17 dangerous diseases through age 2. In fact, vaccines prevent approximately 10.5 million cases of infectious illness per year and save 33,000 lives in the United States alone. 

Click on the diseases listed below to learn which vaccines are recommended and why.


Why Follow The Recommended Vaccination Schedule?

The CDC’s recommended schedule (Birth through 6 years old) is the ONLY vaccination schedule in the U.S. that is rigorously tested for safety and effectiveness.  This same schedule is also recommended by the American Academy of Pediatrics (AAP) and the American Academy of Family Physicians (AAFP).

The vaccines recommended in the CDC schedule are carefully timed to provide protection to children when they are most vulnerable to diseases, and when the vaccines will produce the strongest response from the child’s immune system. It is therefore very important to follow the schedule as closely as possible.

Commonly-Asked Questions About Vaccines for Babies and Children

Vaccines do not cause autism. Nearly a dozen studies following millions of children conducted worldwide over the last decade have failed to find a connection between autism and childhood vaccines. In fact, the original, very small study that claimed to find a connection has been officially retracted by the publication when it was found the lead author, Dr. Andrew Wakefield, lied about his findings. He has since lost his license to practice medicine.

Both the medical and public health communities that monitor vaccine safety have heard the claims of a vaccine-autism link, researched them extensively, and repeatedly disproved them. We encourage you to look at the evidence yourself by reading the many studies that have been done on this topic.

Parents can be confident that the medical and public health communities, including the prestigious National Academy of Medicine (NAM) (formerly known as the Institute of Medicine or IOM), the American Academy of Pediatrics (AAP), the American Medical Association (AMA), the World Health Organization (WHO), the National Institutes of Health (NIH), the Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and many many others, strongly support the safety and benefits of immunizations.

Learn more about this issue and the promising science on autism at the Autism Science Foundation website.

Alison Singer is the mother of a child with autism. Watch this video below as she describes her own personal journey to becoming an autism advocate and investigating the alleged connection between autism and the MMR vaccine.

Get more of your questions about vaccines answered by visiting our Questions About Vaccines section.

Check out CDC’s great animated video that will tell you what to expect when your children get their vaccines.

The Centers for Disease Control and Prevention’s (CDC) recommended immunization schedule for children is specific, and with good reason. Vaccines are recommended for very young children because this is when they are most vulnerable to serious, life-threatening diseases. The recommended schedule is designed to protect your child by providing immunity early in life, before he or she is exposed to dangerous diseases, and when the vaccines will produce the strongest response from your child’s immune system. Delaying a child’s vaccinations just increases the time that he is susceptible to dangerous, and potentially life-threatening diseases.

As your child is growing and adapting to his new world, so is his or her immune system. From the time your baby is born, the immune system begins fighting off millions of germs (bacteria and viruses). Newborns may be immune to some infections because they’ve received antibodies from their mothers, but that protection begins to fade in the first months of life, leaving the baby vulnerable to infectious diseases. Even breastfed babies need to be protected with vaccines at the recommended ages. While breast milk provides important protection from some infections (colds, ear infections and diarrhea), it does not protect children against all diseases. Your baby needs the long-term protection that can only come from making sure he or she receives all his vaccines according to the CDC’s recommended immunization schedule.

How do they determine the ages when children should receive each vaccine? Is it okay to delay vaccines?

Get more of your questions about vaccines answered by visiting our Questions About Vaccines section.

The Centers for Disease Control and Prevention (CDC) sets the U.S. immunization schedules for children, teens, adults and pregnant women based on recommendations from the Advisory Committee on Immunization Practices (ACIP). The ACIP is a group of independent medical and public health experts who carefully review all available data about each vaccine from clinical trials and other studies to develop vaccination recommendations for children, adolescents and adults (including pregnant women).

Before making any recommendations, the ACIP reviews extensive research on the safety and effectiveness of each vaccine. The group’s recommendations include the age(s) when the vaccine should be given, the number of doses needed, the amount of time between doses, and precautions and contraindications. The ACIP examines both the safety and effectiveness of the vaccine given alone, as well as given in combination with other vaccines on the schedule.

The ACIP meets three times a year to make recommendations for new vaccines and to make changes, if needed, to recommended vaccinations based on the latest science and research. The recommended immunization schedules for all ages are reviewed and updated, if needed, every year.

The CDC’s Recommended Childhood Immunization Schedule (from birth to 18 years old) is the ONLY vaccination schedule for children and teens that is rigorously tested for safety and effectiveness. Therefore, it is very important to follow this schedule. The CDC’s schedule is also endorsed by the leading medical groups including the American Academy of Pediatrics (AAP) and the American Academy of Family Physicians (AAFP). The vaccines in the schedule are carefully timed to provide protection to your child when he or she is most vulnerable to, and before he is exposed to, dangerous diseases. Also, vaccines are recommended to be given when they will produce the strongest response from your child’s immune system.

View the 2018 Binational (Mexico and USA) Immunization Resource Tool for Children Birth Through 18 Years

How do they determine the ages when children should receive each vaccine? Is it okay to delay vaccines?

Get more of your questions about vaccines answered by visiting our Questions About Vaccines section.

Yes. Some vaccine-preventable diseases like flu, whooping cough and measles still cause a lot of illness, hospitalizations and even death in the U.S.  And even though other vaccine-preventable diseases that we protect against are rarer in the U.S., they still occur around the world, and unvaccinated travelers can easily bring these diseases with them to the U.S., putting unvaccinated people of all ages at risk of serious illness.

Also, all vaccine-preventable diseases are not the same – some are more deadly than others; and some are more contagious than others. But whether the chance of getting sick or dying from a particular disease is 1 in 100 or 1 in 10,000, you must decide if the risk is worth taking with your children’s health. No one ever thinks that their child will be the 1 in 10,000 that will die from the vaccine-preventable disease.

Get more of your questions about vaccines answered by visiting our Questions About Vaccines section.

Vaccines are one of the most thoroughly tested medical products available in the U.S. Before a vaccine can be considered for approval by the FDA, a vaccine manufacturer must show it is safe and effective through clinical trials. Developing a new vaccine begins with exploratory stage and pre-clinical stage before advancing to three stages of clinical trials. Together, this scientific process can take over a decade and cost millions of dollars. The FDA then examines these studies and determines whether a vaccine is safe, effective, and ready to be licensed for use. The FDA only licenses vaccines that have data that shows that the vaccines’ benefits outweigh the potential risks. If there is any question about the data, or any holes in the data, the FDA will request further studies before approving the vaccine.

After a vaccine is licensed for use in the U.S., there are four systems in place that work together to help scientists monitor the safety of vaccines and identify any rare side effects that may not have been found in clinical trials. Even large clinical trials may not be big enough to find very rare side effects. For example, some side effects may only happen in 1 in 100,000 or 1 in 500,000 people. Second, vaccine trials may not include certain populations like pregnant women or people with specific medical conditions who might have different types of side effects or who might have a higher risk of side effects than the volunteers who got the vaccine during clinical trials.

Vaccine Adverse Events Reporting System (VAERS)

VAERS is a passive reporting system. That means it relies on individuals to report vaccine reactions. Anyone can report a reaction or injury, including healthcare providers, patients and patients’ representatives, such as caregivers or attorneys. The system is co-managed by the FDA and the CDC. However, it is important to note that VAERS data alone can’t be used to answer the question, “Does a certain vaccine cause a certain side effect?” This is because adverse events reported to VAERS may or may not be caused by vaccines. There are reports in VAERS of common conditions that occur just by chance after vaccination. Further investigation may find no medical link between vaccination and these conditions. Instead, the purpose of VAERS is to see if unexpected or unusual patterns emerge, which may indicate a vaccine safety issue that needs to be researched further.

The Vaccine Safety Datalink (VSD)

Established in 1990, VSD is a collaboration between the CDC’s Immunization Safety Office and eight health care organizations across the country. It conducts studies based on questions or concerns raised from the medical literature and reports to VAERS. In addition, when new vaccines are recommended or if changes are made in how a vaccine is recommended, VSD will monitor the safety of these vaccines.

The Clinical Immunization Safety Assessment Project (CISA)

CISA, which was created in 2001, is a national network of vaccine safety experts from the CDC’s Immunization Safety Office, seven medical research centers and other partners. CISA addresses vaccine safety issues, conducts high quality clinical research and assesses complex clinical adverse events following vaccination. CISA also helps to connect clinicians with experts who can help consult on vaccine safety questions related to individual patients.

The Post-Licensure Rapid Immunization Safety Monitoring System (PRISM)

PRISM is a partnership between the FDA’s Center for Biologics Evaluation and Research and leading health insurance companies. It actively monitors and analyzes data from a representative subset of the general population. PRISM links data from health plans with data from state and city immunization information systems (IIS). PRISM has access to information for over 190 million people allowing it to identify and analyze rare health outcomes that would otherwise be difficult to assess.

Download VYF’s handout – How Do We Know Vaccines are Safe?

Download the CDC’s The Journey of Your Child’s Vaccine infographic. You can also watch the CDC’s The Journey of Your Child Vaccine video below.

Get more of your questions about vaccines answered by visiting our Questions About Vaccines section.

You may have heard that vaccines contain all types of crazy ingredients that sound as though they don’t belong in a medical product. The truth is that a very small group of very vocal, but misinformed, individuals have made false accusations regarding the safety of vaccines and their ingredients. In most instances these allegations are just incorrect. In other cases, the claims are misinformed or taken out of context.

The main ingredients in vaccines are antigens, which are small amounts of the bacteria or virus against which the person is being vaccinated. Antigens are the parts of the vaccine that encourage your immune system to create antibodies to fight against future infections. To make sure that the vaccines cannot cause the disease you are trying to protect against, the antigens are altered or weakened. Learn more about how vaccines are made and how they work.

Like many of the foods we eat and beverages we drink, vaccines also contain a small amount of additional ingredients, and each has a specific, necessary function. These ingredients may be added to the vaccine to make it more effective, sterile and/or safe. These additional ingredients have been studied and are safe for humans in the amount used in vaccines.

In fact, the amount of these additional ingredients in vaccines is much less than children encounter in their environment, food and water. As the saying goes, “the dose makes the poison.” In other words, any chemical – even water or oxygen – can be toxic or even deadly in large enough quantities.

Sometimes a child may be sensitive to one of the components of a vaccine, and an allergic reaction may result. For this reason, you should discuss any allergies your child may have with your healthcare provider. Below are the ingredients that may be found in certain vaccines and their purpose:


When an individual vaccine dose is drawn from a multi-dose vaccine vial with a fresh needle, it is possible for bacteria or fungus to get into the vial, which could be very dangerous. To prevent this contamination, a preservative is added to the vaccine.


Thimerosal is an ethylmercury-based preservative used in multi-dose vials of vaccines to prevent contamination. If someone were to receive a vaccine contaminated with bacteria, it could be deadly.

Ethylmercury is very different than methylmercury, which is found naturally in the environment, and what people commonly think of when they hear the word “mercury”. The low levels of ethylmercury in vaccines are broken down by the body differently and clear out of the blood more quickly than methylmercury. A buildup of methylmercury in the body is usually due to eating certain types of fish or other food, and high amounts can harm the nervous system. Over a lifetime, everyone is exposed to some methylmercury.

Even though there was no evidence that thimerosal in vaccines was dangerous, in 1999, it was removed from vaccines in the U.S. in an effort to reduce overall mercury exposure among infants. To keep vaccines safe from contamination without the use of thimerosal or other preservatives, they were either reformulated or put into single-dose vials. Now, the only vaccines in the U.S. that use thimerosal as a preservative are flu vaccines in multi-dose vials. (Thimerosal-free, single-dose vials of flu vaccine are also available in the U.S..) Thimerosal in multi-dose vials is necessary because each time an individual dose is drawn from a multi-dose vial with a new needle and syringe, there is the potential for contamination. There is no evidence that the small amounts of thimerosal in flu vaccines cause any harm, except for minor reactions like redness and swelling at the injection site.

To learn more about the thimerosal content in FDA-approved seasonal flu vaccines, visit the Thimerosal and Vaccines page on the the Food and Drug Administration (FDA) website. MMR (measles, mumps, and rubella), chickenpox (varicella), inactivated polio (IPV), and pneumococcal conjugate vaccines (PCV) NEVER contained thimerosal as a preservative.

No credible scientific studies have found an association between thimerosal in vaccines and autism. The studies used different methods to find out if there was any connection between thimerosal and autism. Some examined rates of autism a state or a country, comparing autism rates before and after thimerosal was removed as a preservative from vaccines. It is important to note that in the U.S. and other countries, the number of children diagnosed with autism has not gone down since thimerosal was removed from childhood vaccinesTo read the studies yourself, visit our Vaccine Research page.


Formaldehyde is a colorless gas that is a byproduct of metabolism so it is already present in the human body. People also encounter formaldehyde every day in the environment. It is used in making building materials and many household products, and formaldehyde also gets into the air through car tailpipe emissions.

Formaldehyde is used is used to inactivate bacterial products for toxoid vaccines (DTaP and Tdap), and to kill unwanted viruses and bacteria that might contaminate the vaccine during the manufacturing process. Most formaldehyde is removed from the vaccine before it is packaged. In trace amounts, formaldehyde is not dangerous. In fact, there is more formaldehyde in a pear than in any one vaccine.


For over 75 years, aluminum gels or salts have been added as adjuvants to some vaccines to improve the vaccine’s abilities to help stimulate the body’s immune system. Without the use of an adjuvant, healthcare providers would need to give more shots in a vaccine series or face lower immunity from the vaccine, and therefore less protection from the disease. Aluminum is also commonly found in food, water, infant formula and even breast milk.


Adjuvants, such as aluminum, are added to certain vaccines to help trigger a better immune response. Without the adjuvant, we would need to administer more shots in the vaccine series or face lower immunity from the vaccine and therefore, less protection from the disease. Studies have shown there is no connection between adjuvants and the development of autoimmune diseases.

Residual Antibiotics

Antibiotics are added to some vaccines to prevent the growth of bacteria during the vaccine manufacturing process and storage of the vaccine. No vaccine produced in the United States contains penicillin.

Egg Protein

Some vaccines, like MMR and some flu vaccines, are prepared in eggs which means that some egg proteins are present in the final vaccine product. The egg proteins help manufacturers to grow enough of the virus or bacteria needed to make the vaccine. Based on scientific evidence, the American Academy of Pediatrics (AAP) states that the MMR vaccine can be safely given to all patients with egg allergies, including patients with a history of severe, generalize anaphylactic reactions to eggs.  AAP also states that “children with egg allergy can receive influenza vaccine with no additional precautions than those considered for any vaccine.”  Additionally, the American Academy of Allergy, Asthma & Immunology (AAAAI) states “Studies show that flu vaccines can be safely administered to egg allergic individuals.” If you or your child are allergic to eggs, make sure to tell your doctor or healthcare provider before getting vaccinated.


Some vaccines contain gelatin to protect them against freeze-drying or heat during the transportation and storage process. People with severe allergies to gelatin should talk to their doctor or healthcare provider before getting vaccinated.


You may have heard that vaccines contain products such as antifreeze. This is not true. Antifreeze typically contains ethylene glycol, an unsafe and highly toxic (poisonous) component, or propylene glycol, a safer and less toxic option to ethylene glycol. Neither of these members of the glycol family of compounds is used in vaccines. In vaccines, polyethylene glycol is used to inactivate the virus in some influenza vaccines and is also used to purify other vaccines. Polyethylene glycol is approved by the FDA and considered non-toxic for medical and other uses.* It is used in a variety of products including skin cream, toothpaste, lubricating eye drops, laxatives, and as an anti-foaming agent in food. It is also used as an irrigating solution in surgical procedures.

Victor O. Sheftel (2000). Indirect Food Additives and Polymers: Migration and Toxicology. CRC Press, 1114-1116.

Read more about ingredients in vaccines and why they are in there.

Get more of your questions about vaccines answered by visiting our Questions About Vaccines section.

Even breastfed babies need to be protected with vaccines at the recommended ages. While breast milk provides important protection from some infections like colds, ear infections and diarrhea, breast milk will not protect him or her against all diseases.

Your baby needs the long-term protection  that can only come from making sure he or she receives all his vaccines according to the recommended immunization schedule, before she is exposed to diseases.