The start of school means it’s vaccine time, and a new 667-page report released today from the Institute of Medicine should offer parents some reassurance. It found that there is no connection between the vaccine for measles, mumps, and rubella (MMR) and autism, despite some parent’s lingering concerns. And it said that other serious side effects of that and other childhood vaccines were rare.
A committee of experts convened by the IOM culled through more than 12,000 peer-reviewed articles to examine whether eight childhood vaccines caused adverse events. The report specifically ruled out any causal relationship between the flu shot and Bell’s Palsy, and found that getting vaccinated against the flu doesn’t make asthma worse. It also dispelled any notions of a connection between the diptheria-tetanus-acellular pertussis (DTaP) vaccine or the MMR vaccine and type-1 diabetes.
Committee chair Ellen Wright Clayton, professor of pediatrics and law at Vanderbilt University, said in a statement:
With the start of the new school year, it's time to ensure that children are up to date on their immunizations, making this report's findings about the safety of these eight vaccines particularly timely...The findings should be reassuring to parents that few health problems are clearly connected to immunizations, and these effects occur relatively rarely. And repeated study has made clear that some health problems are not caused by vaccines.
The report found that only 14 specific health outcomes had convincing evidence linking them to vaccines—and most of those were rare. The committee’s findings about those side effects include:
• The MMR vaccine can lead to fever-triggered seizures in some patients, but almost always without long-term consequences. It can also lead to a rare form of brain inflammation in some people with severe immune deficiencies.
• The chickenpox vaccine (varicella) can cause brain swelling, pneumonia, hepatitis, meningitis, shingles and chicken pox in a minority of immunocompromised patients, as well as in some people with normal immune systems.
• The MMR vaccine, and those for chicken pox, the flu, hepatitis B, meningitis, and tetanus, can trigger anaphylaxis, a serious allergic reaction that can appear shortly after injection.
• Injections of vaccines in general can trigger fainting and inflammation at the injection site.
The committee also found links between the MMR vaccine and short-term joint pain in some women and children, and between the human papilomma virus (HPV) vaccine and anaphylaxis. But the data was less convincing that the vaccines caused those problems.
The results of the report will help guide decisions made under the Vaccine Injury Compensation Program, which pays damages to those injured by vaccines.
Bottom line: Our medical experts say that childhood vaccines do far, far more good than harm. See our advice on the shots that kids and adults need.
Adverse Effects of Vaccines: Evidence and Causality [Institute of Medicine]