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Expert Q&A: Childhood Vaccine Safety

Do vaccines cause autism?

The scientific evidence is clear that vaccines do not cause autism. The Institute of Medicine, IOM, issued a report in 2004. ... Studies since 2004 have continued to find no increased risk of autism following vaccination, including a study we published in Pediatrics in September.

Is it dangerous for kids to be getting so many vaccines at once?

The available scientific data show that simultaneous vaccination with multiple vaccines has no adverse effects on the normal childhood immune system.

A number of studies have been conducted ... and these studies have shown that recommended vaccines are as effective in combination as they are individually and that such combinations carry no greater risk for adverse side effects.

So no evidence suggests that the recommended childhood vaccines can, quote, overload the immune system.

Are the combination vaccines safe?

Combination vaccines have been used since the mid-1940s. ... They have been used for many years without evidence of adverse effects and just as effectively as giving them singly.

There are a few exceptions. The most notable is the MMRV: measles, mumps, rubella, and varicella all in one.  Febrile seizures can occur more frequently with a combination MMRV than when MMR and V are administered as separate injections.

So are they recommended as separate injections?

That is kind of left to the physicians. A clinician should explain the risks and benefits carefully with the child's parents. If they think the parent may not understand, there is a suggestion to give the MMR and varicella separately.

How will I know if my child is having a bad reaction?

If it's any unusual condition such as a high fever [over 100], weakness, or behavioral changes that are particularly concerning to the parent, such as the child is unresponsive ... the ones to really look out for are signs of a serious allergic reaction, and these can include difficulty breathing, hoarseness or wheezing, hives, weakness, a fast heartbeat, or dizziness.

They should call the doctor and get to the [child's] personal doctor right away.

If your kid is sick, should you get vaccinated or wait?

A child with a mild common illness such as a cold or a low-grade fever does not have to wait to be vaccinated. It is preferable to delay vaccination for a child with a more severe illness.

If they have just the sniffles or mild diarrhea, it would be OK to vaccinate.

If my child is taking medications on a regular basis, such as for ADHD, or steroids, are there interactions with vaccines I need to be concerned about?

The parent should consult with their health care provider before getting that vaccination. But in general the commonly used medications, including those for ADHD, are not known to have powerful interactions with vaccinations.

Short-term steroid therapy is usually not a contraindication to administer live virus vaccines. ... There's no evidence of increased severity of reactions to live attenuated vaccine that's been reported among people receiving corticosteroid therapy by aerosol ... so that sort of therapy is not a reason to delay.

Higher doses or longer-term treatment, someone probably being treated for a fairly chronic or severe medical condition, should consult with their health care provider before being vaccinated.

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