FAQs

Marion Sills, MD
Children’s Hospital Colorado
Parent of 3

I get this question all of the time as a doctor. Vaccines are safe, effective and beneficial. Like any medication, vaccines can cause side effects. For the most part the side effects are minor (like a low-grade fever) and go away within a few days. Serious side effects, such as severe allergic reaction, are extremely rare and doctors and clinic staff are trained to deal with them. As an emergency physician, I regularly see cases that remind me how severe vaccine-preventable illness can be, and I cannot recall the last time I saw a serious side effect from a vaccination. As parents, it is intimidating to expose our children, especially infants, to risk. I tell my patients the same thing I know from caring for my own children: the risks and possible side effects are tiny compared to the huge risk of not vaccinating.

Martha Middlemist,
Pediatrics 5280
Parent of 2

Yes. Even if your child receives several vaccines in one day, vaccines contain only a tiny amount of antigens compared to the antigens your child encounters every day! This is also the case if your child receives combination vaccines. Combination vaccines take two or more vaccines that could be given individually and put them into one shot. Children get the same protection as they do from individual vaccines given separately—but with fewer shots. Combination vaccines reduce the number of shots and office visits your child would need, which not only saves you time and money, but also is easier on your child. Some common combination vaccines are Pediarix®, which combines DTap, Hep B, and IPV (polio), and ProQuad®, which combines MMR and varicella (chickenpox). There is overwhelming evidence that giving vaccines, separately or in combination,  raises the child’s immunity. So other than a few extra pokes non-combination vaccines are also very effective.

Matt Dorighi MD,
Cherry Creek Pediatrics

There are 14 vaccine-preventable diseases you can protect your child from before the age of two! Many vaccine- preventable diseases can be serious, or even deadly. Even though many of these diseases are rare in this country, they still occur here and around the world. Unvaccinated U.S. residents who travel abroad can bring these diseases to the U.S., putting unvaccinated children at risk. We have attained “community immunity” for many diseases in the United States, which means that a sufficient proportion of our population is immune to an infectious disease (through vaccination and/or prior illness) to make its spread from person to person unlikely. So, what if we stopped vaccinating here? Diseases that are almost unknown would stage a comeback. Before long we would see epidemics of diseases that are nearly under control today. More children would get sick and more would die.  We don’t vaccinate just to protect our children. We also vaccinate to protect our grandchildren and their grandchildren. We vaccinate to protect our future. Our children don’t have to get smallpox shots anymore because the disease itself no longer exists! Smallpox is now only a memory, and if we keep vaccinating against other diseases, the same may someday be true for them. Vaccinations are one of the best ways to put an end to the serious effects of certain diseases.

Leisha Andersen, MD, MPH,
Colorado Chapter of the American Academy of Pediatrics

Observing vaccinated children for many years to look for long-term health conditions before the vaccine is used routinely is not practical, and withholding an effective vaccine from children while long-term studies are being done wouldn’t be ethical. Instead, we have several systems that look at vaccine reactions continuously to ensure that vaccines remain safe.  In addition, we look at health conditions themselves and at the factors that cause them. Scientists are working to identify risk factors that can lead to conditions like cancer, stroke, heart disease, and autoimmune diseases such as lupus or rheumatoid arthritis. Thousands of studies have already been done looking at hundreds of potential risk factors. If immunizations were identified as a risk factor in any of these studies, we would know about it. So far, they have not.

David Keller, MD,
University of Colorado School of Medicine and Children’s Hospital Colorado
Parent of 2

Yes. Vaccines contain ingredients, called antigens, which cause the body to develop immunity. Vaccines also contain very small amounts of other ingredients. All ingredients either help make the vaccine, or ensure the vaccine is safe and effective. Some of my new patients – and even parents I casually run into at my kids’ school – want to know about the ingredient thimerosal (a mercury-containing preservative). They have heard that it might be related to autism. This is scientifically false. Numerous scientists and researchers have studied and continue to study thimerosal, and they all reach the same conclusion: there is no link between thimerosal and autism. Furthermore, the only childhood vaccines used routinely in the United States that contain thimerosal are flu vaccines in multi-dose vials. 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.

Sara Tisdale, MD,
Mountain View Medical Group

Yes, vaccines are safe and effective. The United States’ long- standing vaccine safety system ensures vaccines are as safe as possible. In fact, currently, the United States has the safest vaccine supply in its history. Safety monitoring begins with the U.S. Food and Drug Administration (FDA), who ensures the safety, effectiveness, and availability of vaccines for the United States. Before the FDA approves a vaccine for use by the public, highly trained FDA scientists and doctors evaluate the results of studies on the safety and effectiveness of the vaccine. FDA also inspects the sites where vaccines are made to make sure they follow strict manufacturing guidelines.

Edward Maynard MD,
Iron Horse Pediatrics

Yes. Vaccines do not overload the immune system. Every day, a healthy baby’s immune system successfully fights off thousands of germs. Even if babies receive several vaccinations in one day, vaccines contain only a tiny fraction of the antigens they encounter every day in their environment. As one doctor put it, “Worrying about too many vaccines is like worrying about a thimble of water getting you wet when you are swimming in an ocean.” Remember that vaccines give your child the antibodies they need to fight off serious vaccine-preventable diseases!

Deborah Archer, MD
Colorado Chapter of the American Academy of Pediatrics and Sunrise Adelante Community Health Center Board Member

They come close, but vaccines are not 100% effective. Depending on the vaccine, about 1% to 5% of children who are vaccinated fail to develop immunity. If these children are exposed to that disease, they could get sick. Sometimes giving an additional vaccine dose will stimulate an immune response in a child who didn’t respond to 1 dose. For example, a single dose of measles vaccine protects about 93% of children, but after 2 doses, about 97% are immune. This is why, in addition to getting all of the recommended vaccines, it is important to get all of the doses needed for each vaccine. Sometimes a child is exposed to a disease just prior to being vaccinated, and gets sick before the vaccine has had time to work. Sometimes a child gets sick with something that is similar to a disease they have been vaccinated against. This often happens with flu. Many viruses cause symptoms that look like flu, and people even call some of them flu, even though they are really something else. Flu vaccine doesn’t create immunity to these viruses.

Deborah Archer, MD
Colorado Chapter of the American Academy of Pediatrics and Sunrise Adelante Community Health Center Board Member

Yes. Unless your child has a specific health condition (such as Guillain-Barré Syndrome), your child needs to get every vaccination. Some parents ask me about the low rates of vaccine-preventable diseases. If the occurrence is low, they very reasonably wonder what the real benefit of vaccination is to their child. It is true that statistically, the chances of any particular child getting measles, pertussis, or another vaccine-preventable disease might be low. But you don’t wear a seatbelt because you expect to be in a serious accident; you wear it because you want to be protected in the unlikely event that you are. If you’re never in an accident, the benefit of wearing a seatbelt might be zero. But if you are, the consequences of not wearing it can be very high. Your child needs a chickenpox vaccine for example, because chickenpox can actually be a serious disease. In many cases, children experience a mild case of chickenpox, but other children may have blisters that become infected. Others may develop pneumonia. There is no way to tell in advance how severe your child’s symptoms will be. Before vaccine was available, about 50 children died every year from chickenpox, and about 1 in 500 children who got chickenpox was hospitalized. It is also important to get every recommended dose of each vaccine when they are recommended. This provides your child with the best protection possible. Depending on the vaccine, your child will need more than one dose to build high enough immunity to prevent disease or to boost immunity that fades over time. Your child may also receive more than one dose to make sure they are protected if they did not get immunity from a first dose, or to protect them against viruses that change over time, like flu. Every dose is important because each protects against infectious diseases that can be especially serious for infants and very young children.

Deborah Archer, MD
Colorado Chapter of the American Academy of Pediatrics and Sunrise Adelante Community Health Center Board Member

No. As a parent myself, I like knowing that a vaccine doesn’t make it into my child’s doctor’s office without being  proven safe and effective. In fact, the journey of a vaccine onto the immunization schedule first requires three phases of Food and Drug Administration(FDA) trials. Vaccines that pass FDA license are then put to an advisory committee of various medical and public health professionals. Once a vaccine is approved for recommendation, the FDA and CDC (Centers for Disease Control and Prevention) monitor the vaccine for possible side effects. As much as we can study a vaccine before its release, there are occasions where its release into the public reveals new data. In the event that the new information causes the risks to outweigh the benefits, a new recommendation can be made.