Category: Vaccine Safety

Side Effects and Adverse Events Following Immunizations

Vaccines are safe, but they do have some side effects, mostly mild, and they rarely cause some serious and severe adverse reactions.

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.

To help keep our vaccines safe, it is important that all “clinically important adverse events that occur after vaccination of adults and children” be reported to VAERS, not just the ones that are known to be side effects.

Wait.

Isn’t an adverse event the same as a side effect?

Adverse Events Following Immunizations

To better understand that, let’s first look at how we define an adverse event following immunization (AEFI):

“An Adverse event following immunization (AEFI) is any untoward medical occurrence which follows immunization and which does not necessarily have a causal relationship with the usage of the vaccine. The adverse event may be any unfavourable or unintended sign, abnormal laboratory finding, symptom or disease.”

Classification of AEFIs

So it should be clear that not all adverse events are actually caused by vaccines.

Many are coincidental events that simply occur after a vaccine is given.

What’s the Difference Between Side Effects and Adverse Events Following Immunizations?

Others are true vaccine reactions though, including fever, pain, fainting, and allergic reactions, etc.

“A side effect is any health problem shown by studies to be caused by a vaccine. Like any medication, vaccines can cause side effects. Usually vaccine side effects are minor (for example, a sore arm where a shot was given or a low-grade fever after a vaccine) and go away on their own within a few days.”

Understanding Side Effects and Adverse Events

These are the reactions that we call side effects or adverse reactions of the vaccine.

Still, just because a sign or symptom can be a side effect of a vaccine doesn’t mean that it always will be.

“A vaccine reaction is an individual’s response to the inherent properties of the vaccine, even when the vaccine has been prepared, handled and administered correctly.”

Vaccine reactions – WHO Vaccine Safety Basics

Here are some other definitions:

  • adverse event – Medical occurrence temporally associated with the use of a medicinal product, but not necessarily causally related.
  • adverse reaction/side effect – A response to a drug which is noxious and unintended, and which occurs at doses normally used in man for the prophylaxis, diagnosis, or therapy of disease, or for the modifications of physiological function.
  • unexpected adverse reaction – Not consistent with applicable product information or characteristics of drug.
  • severe adverse event or reaction – are rarely life-threatening and usually do not result in long-term problems
  • serious adverse event or reaction – Any untoward medical occurrence that at any dose is life-threatening, results in death, requires inpatient hospitalization or prolongation of existing hospitalization, or results in persistent of significant disability or incapacity

Does understanding those definitions make it easier to see why you should be skeptical when folks try to scare you with VAERS reports and data from package inserts?

“Reports of all possible associations between vaccines and adverse events (possible side effects) are filed in VAERS. Therefore, VAERS collects data on any adverse event following vaccination, be it coincidental or truly caused by a vaccine. The report of an adverse event to VAERS is not documentation that a vaccine caused the event.”

Guide to Interpreting VAERS Data

They both can include reports about adverse events, not just side effects. So they both include events that can very well be coincidental, and not caused by a vaccine.

So when doing your research about vaccines, focus on real side effects, or things that are known to be caused by vaccines. You will find that most vaccine side effects are mild and that more serious or severe side effects are very rare.

More on Side Effects and Adverse Events

Are There Any Long-Term Studies On Vaccine Safety?

Vaccines are evaluated for safety in studies when they get approved.

Is that enough?

“I would like to see us do more long-term safety research studies on these large groups of children, so then we can determine that they are safe in the long-term.”

Bob Sears

Apparently not for everyone…

Are There Any Long-Term Studies On Vaccine Safety?

Of course, vaccines continue to be evaluated for safety after they approved, using passive and active vaccine safety systems and long-term post-marketing safety studies.

“We learn about a vaccine’s safety during clinical trials before it is licensed, and monitor it continually as millions of doses are administered after it is licensed. We also know there is not a plausible biologic reason to believe vaccines would cause any serious long-term effects. Based on more than 50 years of experience with vaccines, we can say that the likelihood that a vaccine will cause unanticipated long-term problems is extremely low.”

Parents’ Guide to Childhood Immunizations

These long term studies on vaccine safety have looked at:

Have you heard about these studies before?

When they talk about SV40, do anti-vaccine folks mention this long-term study?
When they talk about SV40, do anti-vaccine folks mention this long-term study?

Probably not.

Anti-vaccine folks either aren’t aware of, or just don’t want you to know about these types of long-term studies.

It’s easier to scare you away from vaccinating and protecting your kids if they make you believe that vaccines aren’t tested together, aren’t tested with placebos, aren’t tested vs unvaccinated kids, and aren’t tested for long periods of time.

They are!

More on Long-Term Studies On Vaccine Safety

More Vaccinated vs Unvaccinated Studies

Anti-vaccine folks continue to call for vaccinated vs unvaccinated studies.

A vaccinated vs unvaccinated study that anti-vaccine folks don't talk about...
A vaccinated vs unvaccinated study that anti-vaccine folks don’t talk about…

Not surprisingly, they ignore all of the studies that have already been done.

More Vaccinated vs Unvaccinated Studies

Listening to these anti-vaccine folks, you would actually think that the only vaccinated vs unvaccinated “study” that has ever been done is the survey about homeschoolers that they always talk about

That leaves out a lot of other vaccinated vs unvaccinated studies, including:

Do we need even more studies on vaccinated vs unvaccinated children?

We already know that unvaccinated kids get sick more and they have more severe disease. Who is going to approve of or want to do a study that only puts kids at risk to get a vaccine-preventable disease?

Vaccines are safe, with few risks, and they are obviously necessary.

More on Vaccinated vs Unvaccinated Studies

Do Vaccines Cause Psoriasis?

Even with all of the so-called vaccine-induced diseases that anti-vaccine folks come up with, few people likely think that vaccines cause psoriasis.

Bob Sears is being investigated by the California Medical Board for giving these medical exemptions because he thinks vaccines cause psoriasis.
Bob Sears is being investigated by the California Medical Board for giving these medical exemptions. Were they legitimate?

Some do though…

Do Vaccines Cause Psoriasis?

Bob Sears thinks that these kids shouldn’t be vaccinated because “vaccines can trigger psoriasis or make existing psoriasis worse.”

Dr. Bob did his research and thinks that vaccines are a risk to cause lifelong psoriasis.
Dr. Bob did his research and thinks that vaccines are a risk to cause lifelong psoriasis.

He even provided a list of studies that he thinks support his case.

“Nevertheless, the likely very low incidence of psoriasis following vaccination emphasizes the safe profile and the relevance of vaccination strategies in psoriasis patients, especially in candidates for immunosuppressive treatments.”

Sbidian et al on National survey of psoriasis flares after 2009 monovalent H1N1/seasonal vaccines.

Do they?

“The risk of psoriasis was also increased in subjects who reported a history of a recent infectious episode. The analysis by individual diagnosis pointed to acute pharyngitis as the disease with the strongest association and the only one providing statistically significant results…”

Naldi et al on Family history of psoriasis, stressful life events, and recent infectious disease are risk factors for a first episode of acute guttate psoriasis: results of a case-control study

Let’s see, although I’m not sure he actually read more than the abstracts or understands that guttate psoriasis isn’t the same as plaque psoriasis

  1. Possible Triggering Effect of Influenza Vaccination on Psoriasis – a small group of patients (36) either had an exacerbation of their psoriasis, or new onset of psoriasis (7), within a couple of weeks to months after getting a flu shot.
  2. Psoriasis triggered by tetanus-diphtheria vaccination – a case report of a 50-year-old with chronic psoriasis for 6 years who developed an exacerbation a week after getting a tetanus booster.
  3. Psoriatic skin lesions induced by BCG vaccination – a case report of a 6-month-old who developed a BCG-induced tuberculid-like eruption accompanied by psoriatic skin changes one month after vaccination. They went away without treatment within 3 months.
  4. Guttate psoriasis-like lesions following BCG vaccination – a case report of a 7-year-old who developed guttate psoriasis-like lesions one week after his BCG vaccination. He was treated with steroid creams and the rash went away within three weeks.
  5. New Onset Guttate Psoriasis Following Pandemic H1N1 Influenza Vaccination – a case report of a 26-year-old who developed guttate psoriasis after getting a flu shot. Her rash went away within three weeks.
  6. National survey of psoriasis flares after 2009 monovalent H1N1/seasonal vaccines – a small group of patients (10) who either developed new onset psoriasis or had an exacerbation after getting a flu shot.
  7. Psoriasis vaccinalis; report of two cases, one following B.C.G. vaccination and one following vaccination against influenza – from 1955, two case reports of psoriasis after BCG vaccine and the flu shot.
  8. Family history of psoriasis, stressful life events, and recent infectious disease are risk factors for a first episode of acute guttate psoriasis: results of a case-control study – a case control study that “confirmed that recent pharyngeal infection is a risk factor for guttate psoriasis. It also documented the strong association between guttate psoriasis and a family history of psoriasis. Finally, the study added evidence to the belief that stressful life events may represent risk factors for the onset of psoriasis.” The study doesn’t mention vaccines, but does remind us that “it has been estimated that only one third of cases of guttate psoriasis progress to chronic plaque psoriasis, whereas a history of guttate psoriasis is not frequent in patients with psoriasis.”
  9. Genetic background of psoriasisdoesn’t mention vaccines.

So, none of Bob’s studies were in children, they are mostly about flu shots and the BCG vaccine (which isn’t used in the United States), they are mostly case reports (low on the hierarchy of evidence), and a few don’t mention vaccines…

And most aren’t about chronic psoriasis!

Explaining the Correlation of Psoriasis After Vaccines

Is there anything that might explain the case reports that do show an association between vaccines and psoriasis flares?

“Psoriasis can appear in areas of the skin that have been injured or traumatized. This is called the Koebner [KEB-ner] phenomenon. Vaccinations, sunburns and scratches can all trigger a Koebner response. The Koebner phenomenon can be treated if it is caught early enough.”

National Psoriasis Association on Causes and Triggers

Experts also talk about Th1- and Th17-predominant immunologic responses of flu shots and the BCG vaccine’s Th17 activity. It is known that Th17 cells play a role in psoriasis.

Are there any other studies about vaccines and psoriasis that Dr. Bob left out?

  1. Yellow fever vaccine used in a psoriatic arthritis patient treated with methotrexate: a case report – “A case of yellow fever vaccine used in a 27-year-old Slovenian male with psoriatic arthritis during treatment with methotrexate is described. We demonstrate a positive case, since there were no adverse effects in concurrent administration of yellow fever vaccine and methotrexate.”
  2. Live attenuated varicella vaccine: A new effective adjuvant weapon in the battlefield against severe resistant psoriasis, a pilot randomized controlled trial – a study of 35 patients which found that the “use of chickenpox vaccine with low-dose cyclosporine seems to have value for the treatment of resistant psoriasis.”
  3. [Psoriasis is no obstacle to smallpox vaccination] – (I haven’t found the full article yet, but the title is intriguing, since eczema is a contraindication to getting the smallpox vaccine…)
  4. Factors associated with 2009 monovalent H1N1 vaccine coverage: a cross sectional study of 1,308 patients with psoriasis in France – mentions that more than twice as many people with psoriasis in France got a flu shot than the general population.
  5. Immune response to pneumococcus and tetanus toxoid in patients with moderate-to-severe psoriasis following long-term ustekinumab use – vaccines work when you have psoriasis!
  6. From the Medical Board of the National Psoriasis Foundation: monitoring and vaccinations in patients treated with biologics for psoriasis – addresses vaccination practices for folks with psoriasis.
  7. Challenges in the treatment of psoriasis with biologics: vaccination, history of malignancy, human immunodeficiency virus (HIV) infection, and pediatric psoriasis – actually talks about how UNDERVACCINATION is a challenge in treating kids with psoriasis, as you might have to interrupt therapy to get them caught up!
  8. Vaccinations in patients with immune-mediated inflammatory diseases – is very clear that the “Clinical evidence indicates that immunization of IMID patients does not increase clinical or laboratory parameters of disease activity. Live vaccines are contraindicated in immunocompromized individuals, but non-live vaccines can safely be given.”

The bottom line is that experts that treat people with psoriasis recommend that they be fully vaccinated.

“Psoriasis is a treatable, chronic dermatosis. The very low absolute risk of new-onset or relapsed psoriasis following influenza vaccination should not change its universal recommendation, particularly for patients with psoriasis on immunosuppressive therapy. We present this case to highlight clinical manifestations of this rare association.”

Shi et al on Widespread psoriasis flare following influenza vaccination

There is even talk of development of a vaccine to treat psoriasis!

It should be clear that neither psoriasis nor a family history of psoriasis should be a reason to get a medical exemption for vaccines.

More on Vaccines and Psoriasis