Medical Disclaimer: This information is educational and not a substitute for medical advice. Always consult your healthcare provider for personalized guidance about your family's vaccination needs.
Why Getting the Facts Right Matters
As a parent or caregiver, you want to make the best possible decisions for your family's health. When it comes to vaccinations, you've likely encountered conflicting information from well-meaning friends, social media posts, or online articles that sound convincing but may not be accurate. This flood of mixed messages can make it difficult to know what's truly safe and effective.
Here's what we know with certainty: vaccines are among the most thoroughly researched medical interventions in history, and they've prevented millions of deaths and cases of serious illness. Yet myths and misinformation persist, sometimes causing families to delay or skip vaccines that could protect their children from dangerous diseases.
At Nestwell Health, we believe you deserve clear, evidence-based answers to your questions. This article addresses common vaccination concerns with scientific facts, helping you make informed decisions with confidence. Your questions are important, and we're here to answer them honestly.
Understanding How Vaccines Work
Before we address specific myths, let's look at what vaccines actually do. Vaccines work by training your immune system to recognize and fight specific diseases without making you sick from the actual disease.
When you receive a vaccine, it introduces a harmless piece of a germ (or instructions for your cells to make that piece) into your body. This might be a weakened or inactive form of the virus or bacteria, a small protein from its surface, or genetic instructions that help your cells temporarily produce a protein that triggers immunity. Your immune system responds by creating antibodies – specialized proteins that recognize and neutralize that specific threat.
If you're later exposed to the real disease, your immune system already knows how to fight it quickly and effectively. This means you either won't get sick at all, or you'll have a much milder illness than you would have without vaccination.
This process mimics what happens when you naturally fight off an infection, but without the risks and complications of the actual disease. You get the immune protection without suffering through measles, whooping cough, or other potentially severe illnesses.
Common Vaccination Myths And the Real Facts
Myth 1: Vaccines cause autism.
This is perhaps the most persistent myth, and it's been thoroughly disproven by extensive research. This misconception started with a fraudulent 1998 study that was later retracted, and the doctor who published it lost his medical license due to ethical violations and falsified data.
Since then, numerous large-scale studies involving millions of children across multiple countries have found no link between vaccines and autism. The Centers for Disease Control and Prevention, the American Academy of Pediatrics, the World Health Organization, and virtually every major medical and scientific organization worldwide have confirmed that vaccines do not cause autism.
Autism typically becomes noticeable around the same age children receive certain vaccines, which created a false association. However, research shows that autism develops before birth due to genetic and environmental factors unrelated to vaccination. Children who aren't vaccinated develop autism at the same rate as vaccinated children.
Myth 2: Natural immunity is better than vaccine-acquired immunity.
While it's true that surviving certain diseases provides immunity, this argument overlooks a crucial point: getting the actual disease is far riskier than getting vaccinated.
Measles can cause brain damage and death. Chickenpox can lead to serious skin infections, pneumonia, and brain inflammation. Whooping cough can be fatal in infants. These aren't theoretical risks but rather they're real outcomes that occurred regularly before vaccines became available. Why risk your child suffering through a dangerous disease when vaccines provide protection safely?
Some vaccines actually produce stronger, more reliable immunity than natural infection. The HPV vaccine, for instance, generates a more robust immune response than natural HPV infection. For diseases where natural immunity is strong, vaccines provide that protection without the danger of complications.
Myth 3: Vaccines contain dangerous toxins.
This concern often focuses on ingredients like aluminum, formaldehyde, or thimerosal (a preservative containing mercury). Here's the context that makes these ingredients safe:
Aluminum salts in some vaccines help boost immune response. The amount is tiny—less than what infants naturally consume through breast milk or formula. Aluminum is one of the most common elements on earth, found in food, water, and air. Your body easily eliminates the small amounts in vaccines.
Formaldehyde occurs naturally in your body as part of normal metabolism. The trace amounts used to inactivate viruses during vaccine production are far less than what's already in your bloodstream. A newborn's body contains about ten times more formaldehyde naturally than what's in any vaccine.
Thimerosal has been removed from nearly all childhood vaccines since 2001 out of an abundance of caution, even though extensive research showed it was safe. It's now only present in some multi-dose flu vaccine vials, and thimerosal-free alternatives are widely available. The ethylmercury in thimerosal is processed and eliminated by the body differently than the methylmercury that accumulates in fish and causes concern.
The key principle: dose matters. Water and oxygen are essential for life, yet too much of either can be harmful. The trace amounts of these ingredients in vaccines are carefully studied and monitored to ensure safety.
Myth 4: Giving multiple vaccines at once overwhelms a child's immune system.
Your child's immune system is remarkably capable. Every day, babies encounter thousands of bacteria, viruses, and other antigens in their environment, from the air they breathe, the food they eat, and the surfaces they touch. Their immune systems handle all of this constantly.
The antigens in the entire childhood vaccine schedule combined are a tiny fraction of what children's immune systems manage daily. Today's vaccines are also more refined than older versions: the current vaccine schedule contains fewer antigens overall than the smallpox vaccine alone did decades ago.
Research consistently shows that receiving multiple vaccines simultaneously is safe and doesn't weaken the immune system. In fact, combination vaccines reduce the number of shots children need, making appointments less stressful while providing the same protection.
Following the recommended schedule protects children during their most vulnerable period. Delaying vaccines leaves them unprotected during the months or years when they're most susceptible to serious complications from these diseases.
Myth 5: We don't need vaccines anymore because these diseases are rare.
This reasoning is backwards. These diseases are rare precisely because vaccines work so well. When vaccination rates drop in communities, these diseases return quickly.
We've seen this happen repeatedly. Measles was declared eliminated from the United States in 2000, but outbreaks have occurred in recent years in communities with lower vaccination rates. In 2019, the U.S. experienced over 1,200 measles cases, the highest number in decades, primarily in unvaccinated people.
Many vaccine-preventable diseases still circulate globally. In our connected world, an unvaccinated person can encounter these diseases while traveling or from visitors from other countries. Polio still occurs in some regions. Whooping cough has resurged in areas with declining vaccination rates.
Maintaining high vaccination rates creates "community immunity" (also called herd immunity), which protects vulnerable people who can't be vaccinated, including newborns too young for certain vaccines, people undergoing cancer treatment, and those with compromised immune systems. When you vaccinate your child, you're protecting not just them but also the medically fragile members of your community.
Myth 6: Vaccines don't work because vaccinated people sometimes still get sick.
No vaccine is 100% effective, but this doesn't mean they don't work. Think of vaccines like seatbelts, they dramatically reduce risk without providing absolute protection.
Most vaccines are highly effective. The measles vaccine is about 97% effective after two doses. Even when breakthrough infections occur in vaccinated people, the illness is typically much milder, shorter, and less likely to cause complications or hospitalization compared to unvaccinated people.
Population-level data proves vaccines work. Before the measles vaccine, nearly everyone got measles, with thousands of deaths and cases of brain damage annually in the U.S. After widespread vaccination began, these numbers plummeted by more than 99%. This pattern repeats for every vaccine-preventable disease.
Myth 7: My child is healthy, so they don't need vaccines.
Healthy children are precisely who we want to keep healthy. Many vaccine-preventable diseases cause the most severe complications in previously healthy people.
You can't predict who will experience serious complications. Some healthy children who contract measles develop encephalitis (brain inflammation). Previously healthy teenagers who get meningococcal disease can require limb amputations. Healthy infants can stop breathing from whooping cough.
Vaccination is preventive medicine at its best, protecting your child before exposure occurs. Once your child is sick with a dangerous disease, it's too late to vaccinate against it.
Myth 8: Vaccines cause the diseases they're supposed to prevent.
Most vaccines cannot cause the disease they prevent because they don't contain live, active pathogens. Inactivated vaccines, subunit vaccines, and mRNA vaccines cannot possibly cause infection.
Some vaccines contain weakened (attenuated) live viruses, like the MMR (measles, mumps, rubella) vaccine. These weakened viruses can't cause the actual disease in healthy people. Occasionally, children might develop a mild rash or low fever after MMR, this shows their immune system is responding but this is not the same as getting measles, which carries serious risks.
The oral polio vaccine, which uses weakened live virus, has been replaced in the United States with an inactivated injectable version specifically to eliminate even the extremely rare possibility of vaccine-derived polio.
Myth 9: Vaccine side effects are worse than the diseases.
Serious side effects from vaccines are extremely rare. Most children experience no side effects or only minor ones like soreness at the injection site, mild fever, or fussiness that resolves within a day or two.
The diseases vaccines prevent cause far more severe problems far more often. Before the measles vaccine, measles killed approximately 400-500 people annually in the U.S. and caused permanent brain damage in many others. Whooping cough killed thousands of infants yearly. Polio paralyzed thousands annually.
Every medication and medical intervention carries some risk, including over-the-counter pain relievers. The difference is that vaccines prevent diseases that are far more dangerous than the vaccines themselves. The risk-benefit calculation overwhelmingly favors vaccination.
The Vaccine Adverse Event Reporting System (VAERS) sometimes fuels this myth. VAERS is an important monitoring system, but it accepts any report of any health event that occurs after vaccination, regardless of whether the vaccine caused it. These reports aren't proof that vaccines caused the problems. They're signals for further investigation. Most reported events are coincidental, occurring after vaccination simply by chance timing.
Myth 10: Pharmaceutical companies and doctors push vaccines just to make money.
Healthcare providers recommend vaccines because they prevent suffering and save lives. Pediatricians see the real consequences when children aren't protected, babies hospitalized with whooping cough, children with measles complications, teenagers dealing with HPV-related cancers that were preventable.
Vaccine development and safety monitoring involve thousands of independent scientists and physicians worldwide, not just pharmaceutical companies. Governments, universities, and non-profit organizations conduct vaccine research. These professionals have dedicated their careers to disease prevention, and many remember what medicine was like before vaccines were available.
Financially, vaccines are among the least profitable parts of medical care. The entire childhood vaccine series costs less than treating a single case of bacterial meningitis. If profit were the primary motivation, doctors would prefer treating diseases rather than preventing them.
What the Recommended Vaccine Schedule Actually Protects Against
Understanding which diseases vaccines prevent helps put the importance of vaccination in perspective. The childhood vaccine schedule protects against:
Hepatitis B can cause lifelong liver infection, liver failure, and liver cancer. Infants who contract it have a 90% chance of developing chronic infection.
Rotavirus causes severe diarrhea and dehydration, leading to thousands of hospitalizations and occasional deaths in young children before the vaccine was available.
DTaP vaccine protects against three diseases. Diphtheria creates a thick coating in the throat that blocks airways. Tetanus causes painful muscle spasms and kills about 1 in 10 people who get it. Pertussis (whooping cough) causes uncontrollable coughing fits that can break ribs and is especially dangerous for babies, who may stop breathing.
Hib (Haemophilus influenzae type b) was the leading cause of bacterial meningitis in young children before vaccination, causing death or permanent brain damage in many cases.
Pneumococcal disease causes meningitis, bloodstream infections, pneumonia, and ear infections. It killed thousands of children annually before the vaccine.
Polio paralyzed thousands of children yearly before vaccination. Although eliminated from the U.S., it still occurs in other countries.
MMR vaccine protects against measles (which can cause brain damage and death), mumps (which can cause permanent hearing loss and fertility problems), and rubella (which causes severe birth defects when pregnant women contract it).
Varicella (chickenpox) seems mild to many people, but it causes serious complications including bacterial skin infections, pneumonia, brain inflammation, and death in some cases. It's also more dangerous for adults who weren't infected as children.
Hepatitis A causes severe liver disease and is especially dangerous for people with underlying liver conditions.
Meningococcal disease progresses rapidly and kills 10-15% of those infected despite treatment. Survivors often suffer permanent consequences including limb loss and brain damage.
HPV (human papillomavirus) causes cervical, throat, and other cancers. The vaccine prevents the virus strains responsible for most HPV-related cancers.
Influenza (flu) kills thousands of Americans annually, including previously healthy children. Annual vaccination reduces risk significantly.
Addressing Your Specific Concerns
We understand that reading facts doesn't always resolve underlying worries. Here are some additional concerns parents commonly share:
"I'm worried about what's not known yet about long-term effects."
Vaccines are monitored for safety longer and more carefully than almost any other medical product. Long-term safety data spans decades for most childhood vaccines. The vaccines your children receive today have been given to hundreds of millions of people worldwide, with extensive tracking of outcomes.
Scientists do understand how vaccines work in the body. Unlike medications taken daily for years, vaccines are given a limited number of times. Your body processes them and develops immunity, then they're gone. There's no biological mechanism by which a vaccine given in childhood could suddenly cause problems years later.
Meanwhile, we have extensive data on the long-term effects of the diseases vaccines prevent and those effects are devastating. Measles can cause subacute sclerosing panencephalitis, a fatal brain disease that emerges years after the initial infection. Chickenpox virus remains dormant in nerve cells and can reactivate decades later as painful shingles. HPV infections can silently persist for years before causing cancer.
"My child has allergies or a sensitive immune system."
Most children with allergies can and should be vaccinated. Vaccine allergies are extremely rare. If your child has a history of severe allergic reactions, your healthcare provider will review the vaccine ingredients and may recommend alternative formulations or take extra precautions during vaccination.
Children with compromised immune systems often need vaccines even more than healthy children because infections pose greater danger to them. Some live vaccines may be contraindicated in severely immunocompromised individuals, but many vaccines are safe and important. Your child's medical team will guide you on which vaccines are appropriate for their specific condition.
"I've heard about vaccine injury compensation, which makes me think vaccines must be dangerous."
The National Vaccine Injury Compensation Program exists not because vaccines are especially dangerous, but because we recognize that no medical intervention is completely without risk and we want to support the rare individuals who experience serious reactions. The program has strict criteria and provides compensation for proven vaccine injuries.
The existence of this program actually demonstrates transparency about vaccine safety. The number of compensated claims is tiny compared to the hundreds of millions of vaccine doses given. Your child is far more likely to be injured in a car accident on the way to the appointment than to suffer serious harm from a vaccine.
What Happens During Your Child's Vaccination Visit
Knowing what to expect can ease anxiety about vaccine appointments. Your healthcare provider will review your child's health history and ask about any allergies or previous vaccine reactions. They'll explain which vaccines are due and answer your questions. You can always ask to see the vaccine information sheet, which lists ingredients and possible side effects.
Most vaccines are given as injections in the thigh (for infants) or upper arm (for older children). Some vaccines can be given at the same visit, reducing the number of appointments needed. The actual vaccination takes just seconds per shot.
Your child might cry from the brief discomfort of the needle, but the pain is momentary. You can comfort your child immediately afterward. Holding infants, breastfeeding, or offering distraction works well for young children. Older children benefit from calm explanations beforehand and praise afterward.
After vaccination, you'll wait 15 minutes in the office to monitor for any rare allergic reactions. Your provider will give you guidance on managing common side effects like soreness or mild fever at home.
Managing Common Side Effects at Home
Most children experience no side effects or only minor, short-lived ones. When side effects occur, they're usually signs that your child's immune system is responding appropriately.
Soreness, redness, or swelling at the injection site is common and typically resolves within a day or two. A cool, clean washcloth on the area can help. Gently moving the arm or leg can reduce stiffness.
Low-grade fever below 101°F (38.3°C) may occur and usually lasts less than 48 hours. Fever after vaccination is not the same as fever from an infection. Keep your child comfortable and ensure adequate fluid intake. You can give acetaminophen or ibuprofen according to your provider's dosing guidance if your child seems uncomfortable. (Note: Some evidence suggests that routinely giving fever reducers before or immediately after vaccination might slightly reduce immune response, so it's best to give them only if your child is uncomfortable.)
Fussiness or decreased appetite might occur for a day or so. Extra cuddles, rest, and patience help. This is temporary.
Mild rash or swelling can develop about a week after MMR vaccine as the immune system responds. This isn't contagious or dangerous and resolves on its own.
Contact your healthcare provider if your child develops high fever above 104°F (40°C), fever that lasts more than 48 hours, serious allergic reactions (difficulty breathing, swelling of face or throat, rapid heartbeat, dizziness), or severe or worsening symptoms at the injection site. These are rare but warrant medical evaluation.
Partnering With Your Healthcare Team
Your child's healthcare providers are your partners in keeping your family healthy. They've spent years studying vaccines, infectious diseases, and child health. They see the benefits of vaccination every day in the healthy children in their practice and in the near-absence of diseases that once filled hospitals.
Come prepared with questions. Write them down beforehand so you don't forget in the moment. No question is too small or silly, if it concerns you, it deserves an answer.
Be honest about your concerns, even if you worry they sound irrational. Your provider can't address worries you don't share. They'll work with you to find accurate information and make a plan you're comfortable with.
Share your family's specific circumstances, including medical conditions, allergies, immune system issues, or previous reactions to vaccines. This information helps your provider give personalized recommendations.
Ask about catch-up schedules if your child has missed vaccines. It's never too late to start vaccinating or to get back on schedule if you've delayed.
Request reliable resources if you want to learn more. Your provider can point you to evidence-based information from reputable medical organizations rather than unreliable internet sources.
Remember, you know your child best when it comes to their personality, temperament, and daily behavior. Your provider brings medical expertise about diseases and prevention. Together, you form a team focused on your child's wellbeing.
Building Community Immunity: Your Role in Public Health
When you vaccinate your child, you're participating in one of public health's greatest achievements. High vaccination rates protect entire communities, especially the most vulnerable members who can't be vaccinated.Newborns can't receive most vaccines until they're a few months old, leaving them vulnerable. Cancer patients undergoing chemotherapy may lose immunity from previous vaccinations. People with certain immune system disorders can't safely receive some vaccines. Elderly individuals may have weakened immune responses even with vaccination.
These community members depend on those around them being vaccinated. When vaccination rates drop below the threshold needed for community immunity (typically 90-95% for highly contagious diseases like measles), outbreaks occur. The disease spreads more easily, reaching those who are most at risk for severe complications.
By vaccinating your child, you're creating a protective buffer
around the medically fragile. You're preventing the spread of dangerous diseases through your community. You're contributing to the possibility that future generations might not have to worry about diseases we currently prevent with vaccines.
What You Can Do Right Now
Taking action strengthens your family's protection and builds your confidence in your vaccination decisions.
Check your child's vaccination record to ensure they're up to date on all recommended vaccines. If you're not sure, your healthcare provider can review their record and identify any needed vaccines.
Schedule any missed or overdue vaccinations. If your child has fallen behind schedule, don't worry, they can catch up. Your provider will create an appropriate catch-up plan.
Ask your provider which vaccines your child will need at upcoming visits so you can mentally prepare and plan your schedule accordingly.
Ensure adults in your household are current on vaccines too, especially whooping cough and flu vaccines if you have a new baby or young infant at home. Adults who spend time with infants should be vaccinated to protect babies too young for their own immunizations.
Keep accurate records of all family members' vaccinations. Many schools, colleges, and workplaces require proof of vaccination, so maintaining organized records saves time and frustration later.
Get reliable information from trusted sources like the Centers for Disease Control and Prevention (CDC), the American Academy of Pediatrics (AAP), and your healthcare provider rather than from social media or non-medical websites.
Frequently Asked Questions
Q: Can I space out vaccines instead of following the recommended schedule?
While this might seem like a reasonable compromise, spreading vaccines out actually increases risks without providing benefits. The recommended schedule is carefully designed based on when children are most vulnerable to specific diseases and when vaccines are most effective. Delaying vaccines leaves your child unprotected during months or years when they're susceptible to serious complications. It also means more clinic visits and more total injections over time. Multiple studies have found no safety advantage to alternative schedules, and spacing out vaccines extends the vulnerable period when children are at risk. If you have concerns about the schedule, discuss them with your provider, but understand that the recommended timing is based on extensive research designed to provide optimal protection.
Q: My child wasn't vaccinated as a baby. Is it too late?
It's never too late to vaccinate. People who missed childhood vaccines can receive catch-up vaccinations at any age. Your healthcare provider will create an appropriate catch-up schedule based on your child's current age and which vaccines they've already received. While it's best to follow the recommended childhood schedule to provide protection early, catching up at any point still provides important disease protection going forward. Don't let past delays prevent you from protecting your child now.
Q: Are vaccines required? What if I choose not to vaccinate?
Most states require certain vaccines for school entry, though exemption policies vary by state. These requirements exist because schools bring together many children in close contact, making disease transmission easy. Requirements protect not just individual children but the entire school community. If you're considering not vaccinating or delaying vaccines, please have an in-depth conversation with your healthcare provider first. They can address specific concerns and help you understand both the risks to your own child and the implications for community health. Choosing not to vaccinate means accepting the risk that your child might contract and suffer complications from preventable diseases.
Q: I've heard vaccines contain aborted fetal cells. Is this true?
This concern is based on a misunderstanding. Some vaccines are made using cell lines that originated from two elective abortions performed decades ago (in the 1960s). These cell lines have been reproducing in laboratories ever since; no new fetal tissue is used. The cells help grow viruses needed for vaccine production. The final vaccines are purified and don't contain any fetal cells or DNA. Even individuals with religious objections to abortion often find this acceptable because the cell lines were established long ago and continue to save millions of lives. However, if this remains a concern, you can discuss it with your healthcare provider and your spiritual advisor. Many religious leaders have affirmed that using these vaccines is morally acceptable given the health benefits.
Q: Why does my child need so many more vaccines than I received as a child?
Medical science has made remarkable progress. We now have safe, effective vaccines preventing diseases that harmed children when you were young. The chickenpox vaccine didn't exist until 1995—before that, nearly every child got chickenpox, and hundreds died from complications yearly. The pneumococcal vaccine introduced in 2000 has dramatically reduced cases of meningitis, blood infections, and pneumonia. These advances are victories, not reasons for concern. The schedule contains more vaccines because we can now prevent more diseases, not because children are weaker or the vaccines are less effective. Today's vaccines are actually more refined, with fewer total antigens despite protecting against more diseases.
Q: What about COVID-19 vaccines for children?
COVID-19 vaccines have been studied in children and are safe and effective at preventing severe illness, hospitalization, and complications including MIS-C (Multisystem Inflammatory Syndrome in Children) and long COVID. Like other vaccines, they underwent rigorous testing before authorization. The decision to vaccinate children against COVID-19 should be discussed with your healthcare provider based on your child's age, health status, and risk factors. These vaccines are recommended by the CDC and AAP for children who are eligible based on age.
When to Seek Care
Schedule a routine well-child visit to discuss your child's vaccination schedule, catch up on any missed vaccines, or address questions and concerns about vaccination. These visits typically occur frequently in the first two years of life, then annually.
Contact your provider's office during business hours if your child develops a fever above 104°F (40°C) after vaccination, has symptoms lasting longer than 48 hours after vaccination, or experiences anything that concerns you after vaccination. While serious reactions are rare, your provider can evaluate and provide reassurance.
Call 911 immediately if your child has difficulty breathing, swelling of the face or throat, rapid heartbeat, dizziness, or other signs of severe allergic reaction within minutes to hours after vaccination. This is extremely rare but requires emergency treatment. (This is why you wait 15 minutes in the office after vaccination—so staff can address any immediate reactions.)
Moving Forward With Confidence
Vaccination decisions matter, and your questions deserve thoughtful, honest answers. The evidence supporting vaccine safety and effectiveness is overwhelming, accumulated through decades of research involving millions of people worldwide. When you vaccinate your child, you're making a choice supported by virtually every major medical and scientific organization, a choice that protects your child and strengthens your entire community.
You don't have to take anyone's word blindly. Ask questions. Seek out reliable information from medical experts and scientific sources. Review the evidence. What you'll find is a consistent message: vaccines are safe, vaccines are effective, and vaccines save lives.
Every parent wants to protect their child from harm. Vaccination is one of the most powerful ways you can do that. The diseases vaccines prevent are not abstract possibilities—they're real threats that harmed and killed children regularly before vaccines became available, and they still harm children in communities where vaccination rates decline.
You have the power to protect your child from these preventable diseases. You have the opportunity to contribute to a healthier, safer community. And you have a healthcare team ready to support you, answer your questions, and partner with you in keeping your family healthy.
Ready to ensure your family is protected? Schedule a vaccination appointment or well-child visit with your Nestwell Health provider to review your child's immunization status and get any needed vaccines.
References
Centers for Disease Control and Prevention. "Vaccine Safety" and "Immunization Schedules." CDC.gov. www.cdc.gov/vaccines
American Academy of Pediatrics. "Childhood Immunization Resources and Safety Information." AAP.org. www.aap.org/immunization
World Health Organization. "Vaccines and Immunization: Myths and Facts." WHO.int. www.who.int/immunization
Institute of Medicine (National Academy of Medicine). "Adverse Effects of Vaccines: Evidence and Causality" (2012). National Academies Press. www.nap.edu
Children's Hospital of Philadelphia, Vaccine Education Center. "Vaccine Ingredients and Vaccine Safety." CHOP.edu. www.chop.edu/centers-programs/vaccine-education-center
Immunization Action Coalition. "Vaccine Information for Healthcare Professionals and Parents." Immunize.org. www.immunize.org
U.S. Food and Drug Administration. "Vaccine Product Approval Process and Safety Monitoring." FDA.gov. www.fda.gov/vaccines-blood-biologics/vaccines