Tag: intussusception

Precautions vs Contraindications When Vaccinating Your Kids

Believe it or not, there are some anti-vaccine folks who believe that all vaccines are dangerous and unnecessary. And they believe that pediatricians push vaccines on kids in all situations, using a one-size-fits-all kind of immunization schedule.

Of course, neither is true.

Vaccines are safe and necessary.

There are some true medical contraindications and precautions to getting vaccinated though. Still, it is important to remember that even more things are simply “conditions incorrectly perceived as contraindications to vaccination.”

Contraindications To Vaccinating Your Kids

There are actually some good reasons to delay or skip one or a few of your child’s vaccines, but only in some very specific situations.

These very specific situations are called contraindications and are what count as medical exemptions.

“A vaccine should not be administered when a contraindication is present; for example, MMR vaccine should not be administered to severely immunocompromised persons.”

CDC on Vaccine Contraindications and Precautions

Fortunately, there are not that many of these contraindications, they are usually specific to just one or a few vaccines, and they are usually, but not always, temporary.

That’s why it would be really unusual to get a true permanent medical exemption for all vaccines. Even if you had a severe allergy to a vaccine that contained yeast, latex, or gelatin, since vaccines contain different ingredients, you would very likely be able to safely get the others.

Remember, your doctor can’t, or at least shouldn’t, just make up contraindications and exemptions to help you avoid getting your kids vaccinated and help you keep them in school.

“I do not believe vaccines had anything to do with my child’s autism. I never noticed any change in his speech, behavior or development with vaccines. I believe the protection and benefits of vaccines far outweigh the risks!”

Michele Han, MD, FAAP

Autism, for example, has been shown to not be associated with vaccines, so it is not a contraindication to getting vaccinated. That’s why many parents vaccinate and protect their autistic kids!

Precautions To Vaccinating Your Kids

In addition to contraindications to getting vaccinated, there is an accompanying list of  precautions.

“A precaution is a condition in a recipient that might increase the risk for a serious adverse reaction, might cause diagnostic confusion, or might compromise the ability of the vaccine to produce immunity (e.g., administering measles vaccine to a person with passive immunity to measles from a blood transfusion administered up to 7 months prior). A person might experience a more severe reaction to the vaccine than would have otherwise been expected; however, the risk for this happening is less than the risk expected with a contraindication. In general, vaccinations should be deferred when a precaution is present. However, a vaccination might be indicated in the presence of a precaution if the benefit of protection from the vaccine outweighs the risk for an adverse reaction.”

CDC on Vaccine Contraindications and Precautions

Again, we are fortunate that most of the conditions that are listed as precautions are temporary.

The vaccine information sheet that you get with each vaccine will list contraindications and precautions on who should not get the vaccine.
The vaccine information sheet that you get with each vaccine will list contraindications and precautions on who should not get the vaccine.

In fact, the most common is having a “moderate or severe acute illness with or without fever.”

Don’t want to get your child vaccinated when he or she has a severe illness?

Don’t worry.

Your pediatrician usually doesn’t want to vaccinate your child in that situation either.

It is easy enough to wait a few days or a week to get vaccinated, when the illness has passed, keeping in mind that a “mild acute illness with or without fever” is neither a precaution nor a contraindication to getting vaccinated. So you can still get your child their recommended vaccines if they just have a cold, stomach bug, or ear infection, etc.

What to Know About Precautions and Contraindications to Vaccines

Although there are some true medical exemptions or contraindications and precautions to getting vaccinated, most are vaccine specific and many are temporary, so they shouldn’t keep you from getting your child at least mostly vaccinated and protected.

More on Precautions and Contraindications to Vaccines

Vaccines and the Risk of Intussusception

Many people first heard the term intussusception after it became associated with Rotashield, the first rotavirus vaccine, back in 1999.

What is Intussusception?

Intussusception is a type of intestinal blockage that occurs when one part of a child’s intestine in pulled into or slides into another.

This leads to younger children, typically between the ages of 3 months and 3 years, developing colicky abdominal pain (severe pain that comes and goes) and loose stools that are filled with blood and mucous.

Fortunately, if caught early, it can be both diagnosed and treated with an air contrast enema.

Do Rotavirus Vaccines Cause Intussusception?

Intussusception in children is not a new condition. In fact, Samuel Mitchel reported treating children with intussusception as early as 1838!

So what causes intussusception?

Surprisingly, in most cases, we just don’t know why kids get intussusception.

We do know that it occurs in about 1 in 100,000 US infants, with about 2,000 cases being diagnosed and treated each year.

“There is also a small risk of intussusception from rotavirus vaccination, usually within a week after the first or second dose. This additional risk is estimated to range from about 1 in 20,000 to 1 in 100,000 US infants who get rotavirus vaccine.”

CDC on Questions & Answers about Intussusception and Rotavirus Vaccine

And we know that getting a rotavirus vaccine adds a small extra risk for intussusception.

The association was found by looking at reports to VAERS and studies by the FDA’s Post-licensure Rapid Immunization Safety Monitoring System (PRISM).

And it is not just the original Rotashield vaccine, which was withdrawn, but the rotavirus vaccines that we now use that have also been linked to intussusception. The difference is that the risk is much less with the newer rotavirus vaccines.

“Given the magnitude of declines in rotavirus disease compared with this small increase in intussusception, the benefits of rotavirus vaccination outweigh the increase risk of intussusception.”

Tate et al on Intussusception Rates Before and After the Introduction of Rotavirus Vaccine

This small risk must also be viewed against the many benefits of the rotavirus vaccines.

“Rotavirus is the leading cause of severe gastroenteritis among young children worldwide, and was estimated to account for approximately one-third of the estimated 578,000 deaths from childhood gastroenteritis and more than 2 million hospitalizations and 25 million outpatient clinic visits among children <5 years of age each year in the pre-vaccine era.”

Parashar et al on Value of post-licensure data on benefits and risks of vaccination to inform vaccine policy: The example of rotavirus vaccines

Rotavirus vaccines are associated with a very small risk of intussusception, but that is not a good reason to miss the benefits of this vaccine.
Rotavirus vaccines are associated with a very small risk of intussusception, but that is not a good reason to miss the benefits of this vaccine. Photo by Vincent Iannelli, MD

It is also still not clear if the rotavirus vaccines actually “trigger” intussusception or if they simply cause it to occur earlier in infants that would have gotten it anyway. That’s because while the latest studies have found excess cases shortly after the first dose of vaccine, studies looking at intussusception trends “have not consistently demonstrated an overall increase in rates post-vaccination.” So there were the same number of total cases, even with the few extra cases right after the kids were vaccinated.

Also, it is thought that wild type rotavirus infections can also trigger intussusception, so the rotavirus vaccines might prevent those cases.

Most importantly though, remember that even if the rotavirus vaccines cause an extra 35 to 100 hospitalizations a year because of intussusception, they are preventing up to 70,000 hospitalizations from severe rotavirus diarrheal disease that occurred in the pre-vaccine era. The vaccines are also preventing about 20-60 deaths from rotavirus disease, while intussusception is rarely life-threatening.

If you are on the fence about vaccines, worry about intussusception is not a good reason to skip or delay your child’s vaccines.

What to Know About Vaccines and Intussusception

Because of a small risk of intussusception, parents should be aware of the symptoms and signs of intussusception and that they may appear six to eight days after an infant’s first dose of rotavirus vaccine.

More on Vaccines and Intussusception

Underreporting of Side Effects to VAERS

Vaccine injuries and side effects should be reported to Vaccine Adverse Event Reporting System (VAERS).

Reporting Side Effects to VAERS

The CDC advises that “all significant adverse events that occur after vaccination of adults and children, even if you are not sure whether the vaccine caused the adverse event.”

Are they?

Unfortunately, no.

Vaccine adverse events can be reported to VAERS online or using a downloadable form.
Vaccine adverse events can be reported to VAERS online or using a downloadable form.

 

While both doctors and parents can report these side effects, they don’t always get reported.

Underreporting of Side Effects to VAERS

Still, although reports to VAERS are underreported, they are almost certainly not underreported by as much as some folks believe.

Have you heard the claim that only 1% of serious vaccine reactions are reported to VAERS?

That’s not true.

That claim is based on an old study about drug reactions and was not specific to vaccines.

We also know that underreporting is less common for more severe adverse reactions than for those that are more mild. For example, one study found that up to 68% of cases of vaccine-associated poliomyelitis (a table injury) were reported to VAERS, while less than 1% of episodes of rash following the MMR vaccine were reported.

That’s not to say that only severe or serious adverse reactions should be reported.

But since VAERS watches “for unexpected or unusual patterns in adverse event reports,” it still works even if each and every side effect isn’t reported.

VAERS Works

Reports to VAERS are underreported.

VAERS still works well though.

Again, that’s because VAERS doesn’t need each and every adverse event to be reported for the system to work and to help it identify vaccines that might not be safe.

“Despite its limitations, VAERS effectively detected a possible problem soon after introduction of RRV-TV in the United States.”

Lynn R. Zanardi, et al on Intussusception Among Recipients of Rotavirus Vaccine: Reports to the Vaccine Adverse Event Reporting System

We saw that with the RotaShield vaccine. After nearly 20 years of research, the first rotavirus vaccine was approved by the FDA on August 31, 1998. About seven months later, in March 1999, the ACIP published their formal recommendations that all infants get RotaShield on a three dose schedule, when they are two, four, and six months old.

By June 11, 1999, VAERS had received 12 reports of intussusception related to the RotaShield vaccine and by July 13, its use was temporarily suspended, as the CDC continued to investigate.

Once the CDC announced the temporary suspension, even more reports of intussusception after RotaShield were made to VAERS. Those extra reports likely mean that intussusception was being underreported initially, but it still triggered the temporary suspension and extra studies that eventually got the manufacturer to withdraw the vaccine.

“VAERS is used to detect possible safety problems – called “signals” – that may be related to vaccination. If a vaccine safety signal is identified through VAERS, scientists may conduct further studies to find out if the signal represents an actual risk.”

CDC on How VAERS is Used

Early signals in VAERS also helped detect a very small increase in the risk of febrile seizures among toddlers who got the 2010-11 flu vaccine combined with either Prevnar or a DTaP vaccine.

Also keep in mind that VAERS isn’t the only system that helps to monitor vaccine safety. We also have the Vaccine Safety Datalink project, the Clinical Immunization Safety Assessment Network, and the Vaccine Analytic Unit.

What to Know About Underreporting of Side Effects to VAERS

Even though underreporting of side effects to VAERS is an issue, because VAERS works by looking at early signals and trends, it still works well to identify possible safety problems from vaccines.

More About Underreporting of Side Effects to VAERS