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Children's Vaccines Health Center

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Side effects from vaccines

Some people question the safety of immunizations for children. Although minor discomfort sometimes follows vaccine injections, research does not support claims that immunizations put a child at any significant risk for harmful side effects. The U.S. Food and Drug Administration (FDA) carefully evaluates all vaccines for safety. Federal law requires health professionals to report any reaction following an immunization to the Vaccine Adverse Events Reporting System (VAERS). Only two vaccines-the 1976 swine influenza vaccine and the old rotavirus vaccine in 1999-have ever been recalled because of safety concerns.

Side effects from vaccines are generally minor, if they occur at all. The area where the shot was given may be sore. And some children may be fussy or get a slight fever. More serious side effects are very rare. The risk of a serious complication from a disease is far greater than the risk from the vaccine.

Recommended Related to Children's Vaccines

Understanding Meningitis -- Prevention

Meningitis is usually caused by many different viruses and bacteria. So the best methods of preventing it varies. But by getting vaccinated and taking sensible precautions, you can greatly reduce your risk. Here's what you need to know about meningitis prevention.

Read the Understanding Meningitis -- Prevention article > >

The U.S. Centers for Disease Control and Prevention (CDC) vaccine information statements list the side effects of each vaccine. For more information, see the topic Vaccine Information Statements.

The CDC and the FDA continue to study vaccines. Although the risk of problems from vaccines is already extremely low, these agencies watch for any reports of rare or unexpected reactions.

Exposure to mercury

In the past, thimerosal, a mercury-containing compound, was added to vaccines to prevent bacterial growth. In 1999, the U.S. Advisory Committee on Immunization Practices (ACIP) responded to concern about this additive's safety and set a goal to have it removed from all childhood vaccines made in the U.S. Even though studies do not show a link between thimerosal and autism or any other condition, all routinely recommended U.S. childhood vaccines contain either no thimerosal or only trace amounts.1

The FDA keeps a list of all vaccines that are given to children and how much, if any, thimerosal the vaccines contain. To view the list, go to


  1. Centers for Disease Control and Prevention (2009). Vaccine safety: Mercury and thimerosal. Available online:

By Healthwise Staff
Primary Medical Reviewer John Pope, MD - Pediatrics
Specialist Medical Reviewer William Atkinson, MD, MPH - Public Health and Preventive Medicine
Last Revised February 26, 2010

WebMD Medical Reference from Healthwise

Last Updated: February 26, 2010
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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