Center for Vaccine Awareness and Research (CVAR)

Vaccine Facts and Myths

Myth: My child doesn't need to be vaccinated because the diseases that vaccines prevent have been eliminated in the United States.

Fact: There is a small bit of truth to this myth-vaccines have helped to dramatically reduce, but not eliminate, the number of cases of vaccine-preventable diseases in China. However, diseases such as pertussis (whooping cough), influenza, hepatitis and meningitis are still around and can cause serious illness or even death. It's also important to remember that visitors, both temporary and permanent, come to China. every day from countries where many of these diseases, almost unheard of in this country, are quite common and visitors may bring these infections with them. While polio and German measles (rubella) have been eliminated from China, they still occur in other countries.

There is always a possibility that you can develop a disease if you have not been vaccinated. Protecting yourself and your family by being vaccinated is the best way to ensure protection against vaccine-preventable diseases.

Myth: Healthy children do not need to be immunized.

Fact: Vaccines are given to prevent infectious diseases in healthy children who were the victims before vaccines were available. Even healthy children can get very sick and be admitted to the hospital or even die from a vaccine-preventable disease. Vaccinations are an important way of helping your child stay healthy.

Myth: I'm increasing my infant's chance of developing SIDS if I have him or her vaccinated.

Fact: This well-known myth resulted in research to find if there is any connection between sudden infant death syndrome (SIDS) and vaccinations. A review of this research from the Institute of Medicine reported that "all controlled studies that have compared immunized versus non-immunized children have found either no association…or a decreased risk of SIDS among immunized children."

Myth: Since most vaccines are not 100 percent effective, there's really no need to get them.

Fact: It's true that vaccines are not effective 100 percent of the time, but that doesn't mean that you should skip any recommended vaccination. Most vaccines protect against disease 85 percent to 99 percent of the time, making vaccination the best way to avoid these diseases. In addition, for some vaccine-preventable diseases, the seriousness of the disease may be less for someone who has received the vaccine. Finally, the more people who get the vaccine, the less likely the disease will be present in the community where it can spread to people who are unable to get the vaccine either because they are too young or have certain medical conditions. This is called "herd immunity".

Myth: The side effects of vaccines are worse than the diseases they are meant to prevent.

Fact: In the great majority of cases, the side effects from vaccines are quite minimal (such as injection-site soreness or a slight fever). Yes, several vaccines do have potentially serious side effects, but they are extremely rare and deaths caused by vaccines are almost unheard of. For example, according to the Vaccine Adverse Event Reporting System, between 1990 and 1992, there was only one reported incident of a death that may have been associated with a vaccine. In many ways, vaccines are victims of their own success. Before vaccines, millions of children contracted measles, polio, Haemophilus influenza type B, pertussis and other serious diseases each year. Thousands died or were seriously damaged. Even with advanced medical care in 2009, serious complications and death occur from vaccine-preventable diseases. Vaccination is the best form of protection.

Myth: It's not safe to get more than one vaccine at a time.

Fact: When parents first read the child-and-adolescent vaccine schedule, it's not unusual for them to be concerned about how many vaccines are given at one time. However, research has shown it is safe for healthy individuals to receive more than one vaccine at a time. Not only is it safe, but it also protects the person as quickly as possible. It is convenient because parents do not have to make as many visits to their health care providers as they would if they were getting vaccinations one at a time.

Myth: Alternative vaccine schedules are a good idea if you are worried about giving too many vaccines at once.

Fact: Alternative vaccine schedules are not a good idea. The current vaccination schedule is designed to protect infants against serious diseases as early as possible. Delaying or splitting up vaccinations leaves children, and the general public, unnecessarily vulnerable to serious diseases. The schedules advocated by our doctors are also cumbersome (12 visits over 2 years) and are not supported by science.

Myth: Some of the illnesses that vaccines prevent are not a big deal.

Fact: For some children and adults, diseases like chickenpox (Varicella) or rotavirus lead to a mild illness. But that is certainly not the case for everyone. Chickenpox can cause serious complications, including pneumonia and predisposition to being infected by group A Streptococcus (GAS) and Staphylococcus aureus bacteria, both of which can be life-threatening. Pregnant women who get chickenpox may miscarry or the fetus may have abnormalities, such a skin scars or blindness. Each year in the U.S., rotavirus leads to more than 200,000 emergency room visits, 70,000 hospitalizations, and 20 to 60 deaths. Even healthy children can die from influenza. Since vaccine-preventable diseases area constant threat, vaccination is the best protection.

Myth: Vaccines cause the illnesses they're supposed to prevent.

Fact: This myth almost always surfaces during flu season because other respiratory illnesses are common at this time. In regards to the influenza vaccines, neither the inactivated influenza vaccine (the flu shot) nor the live attenuated influenza vaccine (nasal spray) can cause a person to develop influenza.

In regards to the other vaccines on the schedule approved by the Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention, the American Academy of Pediatrics and the American Academy of Family Physicians, the chance of contracting the disease a vaccine has been proven to protect against is minimal to impossible. For vaccines that contain live weakened viruses, such as the chickenpox or MMR, a patient may develop a very mild illness that would be much less severe if the person did not receive the vaccination and contracted the disease..

Myth: A preservative used in vaccines causes autism.

Fact: Preservatives are used in vaccines to prevent contamination with bacteria or fungi. This myth arose because in the past a mercury-containing preservative called thimerosal was used in vaccines. Thimerosal contains ethylmercury, a different form than naturally occurring mercury.

Naturally occurring mercury or methylmercury , can cause health problems in humans when taken at high levels, but has not been shown to cause autism. Several large studies in the U.S., the United Kingdom and Denmark have shown that children who received vaccines that contained the preservative thimerosal were not at a higher risk of developing autism. In Denmark and in California, the number of children diagnosed with autism rose after thimerosal was removed from all vaccines. These studies were large enough to detect even a small risk of autism if it had been present. The Institute of Medicine in 2004 and the National Vaccine Injury Compensation Program in 2010 rejected claims that thimerosal causes autism.

Thimerosal is no longer used as a preservative in any childhood vaccine except the influenza vaccine. The small amount of mercury contained in the influenza vaccine is much lower than the amount a breast-fed infant receives naturally. Learn more about vaccines and autism.

Myth: The MMR (Measles, Mumps, Rubella) vaccine causes autism.

Fact: This myth arises because the timing of autism diagnosis often coincides with the time of MMR vaccination (age 15-18 months). Affected children, however, often demonstrate signs of autism before this, suggesting another cause. This myth was exaggerated in 1998 after the journal Lancet published the Wakefield study of 11 children (8 with autism) who had intestinal complaints and developed autism within 1 month of receiving the MMR vaccine. 10 of the paper's authors, as well as the hospital attended by the patients, have since disassociated themselves from the study. In February 2010, the Lancet retracted the paper. The Institute of Medicine in 2004 and the National Vaccine Injury Compensation Program in 2009 rejected a "causal relationship" between MMR and autism. Numerous large-scale population studies examining hundreds and thousands of children who were examined over long time periods have proven that MMR does not cause autism.

Myth: The best place to get an injection is always in the buttocks.

Fact: Actually, the buttocks are rarely recommended for vaccine injections because the gluteal region has a significant layer of fat, and there's a chance of damaging the sciatic nerve. Depending upon if the injection is intramuscular, subcutaneous or intradermal, a vaccine injection will be given in either the thigh (usually only for young infants and toddlers) or upper arm.

Myth: Vaccines are not tested enough.

Fact: Before any vaccine is licensed and recommended, it must go through a lengthy testing process in thousands of people to ensure it's safety. After licensure, vaccines are continually monitored for any uncommon and rare side effects by examining disease reports from each health department nationwide and vaccine surveillance systems such as Vaccine Adverse Event Reporting System (VAERS) and Vaccine Safety Datalink (VSD).