Tag: live vaccines

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

How Much Shedding Would a Vaccine Shed…

Are you still confused about vaccine shedding?

You should be worried about wild diseases, not shedding from vaccines.
You should be worried about wild diseases, not shedding from vaccines.

As this infographic describes, it really isn’t that complicated…

What Does Vaccine Shedding Really Mean?

To clear up some things:

  • yes, some vaccines do actually shed, but it is rarely a reason to avoid getting vaccinated and protected
  • of the vaccines that we use routinely, shedding is limited to the rotavirus vaccines, FluMist, and the chickenpox vaccines
  • some other vaccines that can shed include the oral polio vaccine and the smallpox vaccine
  • the rubella component of MMR may very rarely shed, but only in breastmilk

If vaccines do shed, why shouldn’t we be more concerned about it?

Well, for one thing, most vaccines don’t shed.

DTaP, hepatitis A, hepatitis B, Hib, flu, IPV, HPV, meningococcal, pneumococcal, and Tdap shots – none of them shed.

And then there is the fact that:

  • when a vaccine sheds, it is the weakened or attenuated vaccine strain, not the wild strain that would cause more serious disease. Putting it another way, if the vaccine strain doesn’t make the person who is getting immunized sick, then why would it get someone else sick if they got it through shedding? Of course, there is a situation in which even a vaccine strain could be dangerous, and that’s for those who are severely immunosuppressed. Still, natural disease would be bad for these kids too!
  • even with oral polio vaccines, the problem isn’t really shedding, which actually provides a type of passive immunization in areas where polio is still not well controlled. The problem is that very rarely, the attenuated virus in the oral polio vaccine can revert to a form that can cause the person who was vaccinated to actually develop polio (VAPP). Now, shedding of this strain would be a problem, but only if the other person wasn’t immune.
  • rotavirus vaccines only shed in stool. You can avoid it by washing your hands when you change your child’s diapers, which you hopefully do anyway.
  • FluMist is attenuated and cold-adapted, which means that it won’t replicate well in our warmer nasal passages and respiratory tracts.
  • you have to actually get a rash, which is rare, for the chickenpox vaccine to shed.
  • it is only kids with eczema that usually get sick if they are exposed to someone who recently had the smallpox vaccine. Since the smallpox vaccine causes skin reactions, even the attenuated vaccine strain can cause severe reactions if a child’s skin is already broken down, like with eczema.

Are you still concerned about shedding?

Can a Vaccinated Person Transmit Measles Through Shedding?

To put your mind at ease, understand that you are not going to get measles from shedding.

“In this systematic review, we have determined that there have been no confirmed cases of human-to-human transmission of the measles vaccine virus.”

Greenwood et al on A systematic review of human-to-human transmission of measles vaccine virus

Well, at least not from someone who was recently vaccinated shedding a vaccine-strain of measles

If you aren’t vaccinated and protected, you could easily get it from someone who has measles and who is shedding the wild type virus though. Measles is so contagious, you just have to be in the same room as someone with measles and you will likely get sick. In fact, you can enter a room a few hours after they have left and sill catch measles!

And in theory, if someone developed vaccine-associated measles – they got sick with a vaccine-strain of measles after getting vaccinated – then they could spread the virus to someone who wasn’t immune. That’s just because they would be contagious though, not anything specific to vaccines and shedding. Also, it is basically unheard of for this to happen.

Dectecting vaccine strain measles in urine isn't something to be concerned about because it can't lead to an infection. Measles is spread through respiratory secretions, not urine.
Dectecting vaccine strain measles in urine isn’t something to be concerned about because it can’t lead to an infection. Measles is spread through respiratory secretions, not urine.

What about all of those folks who test positive for vaccine-strain measles during an outbreak?

That’s not about shedding either.

They aren’t even people with measles. Instead, they typically have a vaccine reaction, a rash and/or fever after getting their MMR and they test positive for the vaccine strain of measles because they just got a live virus vaccine.

Is Vaccine Shedding a Threat?

Shedding isn’t the threat that anti-vaccine folks make it out to me.

Think about it. If it really was a big problem, then why don’t more intentionally unvaccinated kids with exemptions get sick when they are around kids who are vaccinated?

“Health officials should require a two-week quarantine of all children and adults who receive vaccinations. This is the minimum amount of time required to prevent transmission of infectious diseases to the rest of the population, including individuals who have been previously vaccinated.”

Sally Fallon Morell, president of the Weston A. Price Foundation

We don’t actually quarantine anyone after they are vaccinated, so why don’t more kids with immune system problems get sick via shedding?

Or just think about what happens in a typical daycare or school. All of the kids don’t get vaccinated on the same day, so if shedding was an issue, wouldn’t the kids who had gotten their vaccines first shed on the ones who weren’t yet vaccinated, getting them sick?

Of course, this doesn’t happen. Again, shedding isn’t the threat that anti-vaccine folks make it out to be.

More on Vaccine Shedding

Dengvaxia for Dengue Fever

Dengvaxia was recently approved by the FDA after being available in other countries since about 2015.

“Indicated for the prevention of dengue disease caused by dengue virus serotypes 1, 2, 3 and 4. DENGVAXIA is approved for use in individuals 9 through 16 years of age with laboratory-confirmed previous dengue infection and living in endemic areas.”

Wait.

Dengue is endemic throughout the tropics and subtropics, including most of the Caribbean.
Dengue is endemic throughout the tropics and subtropics, including most of the Caribbean.

It’s only for people who have already had a dengue infection before?

Dengvaxia Controversy

Unfortunately, Dengvaxia “performs differently in seropositive versus seronegative individuals.”

“In areas of 70% dengue seroprevalence, over a 5-year follow-up, for every 4 severe cases prevented in seropositive, there would be one excess severe case in seronegative per 1,000 vaccinees; for every 13 hospitalizations prevented in seropositive vaccinees, there would be 1 excess hospitalization in seronegative vaccinees per 1,000 vaccinees.”

WHO on Questions and Answers on Dengue Vaccines

If you have never had dengue before and you are vaccinated, you are at risk for a severe infection if you do get dengue. On the other hand, if you are unvaccinated, you are at even greater risk of getting dengue, a life-threatening infection. Fortunately, the first episode of dengue is usually fairly mild.

The problem occurs if your antibody levels have dropped enough, which can cause you to have a severe case of dengue the second time. The process is called antibody-dependent enhancement and has to do with antibody levels, either natural or vaccine induced. So it can occur whether or not you are vaccinated, although getting Dengvaxia, an attenuated, live vaccine, can act as a primary dengue infection.

“These differing epidemiological features support the conclusion that antibody dependent enhanced (ADE) dengue disease occurred in seronegatives who were sensitized by vaccine. As hospitalizations continue to occur in all age groups Dengvaxia consumers should be warned that sensitized vaccinated seronegatives will experience enhanced dengue disease into the forseeable future.”

Scott Halstead on Dengvaxia sensitizes seronegatives to vaccine enhanced disease regardless of age.

It is something that dengue researcher Scott Halstead warned folks about as soon as he saw the first published study on Dengvaxia.

But why would you need a vaccine if you have already had dengue?

“In humans recovery from infection by one dengue virus provides lifelong immunity against that particular virus serotype. However, this immunity confers only partial and transient protection against subsequent infection by the other three serotypes of the virus. Evidence points to the fact that sequential infection increases the risk of developing severe dengue.”

WHO on Dengue control

There are four serotypes of dengue.

So if you aren’t vaccinated, you are at risk to get dengue multiple times.

Tragically, about 800,000 children in the Philippines were given Dengvaxia in a universal immunization program without checking to see if they had dengue first. And it likely led to some severe cases of dengue and deaths. This led to the vaccine being banned in that country and is thought to be one of the causes behind their current measles outbreak, as their Dengvaxia controversy led to more vaccine hesitancy.

And it will lead to more folks getting dengue. Instead of a ban, they should likely be more picky about who they give the vaccine to, either confirming that recipients have already had dengue (titer test) or only giving the vaccine to older kids.

Dengvaxia for Dengue Fever

Do you need Dengvaxia?

Remember, Dengvaxia is only for those living in endemic areas and in the United States, dengue is only endemic in the U.S. territories of American Samoa, Guam, Puerto Rico, and the U.S. Virgin Islands.

Do you need Dengvaxia if you are simply traveling to one of these areas?

Since Dengvaxia is not approved for those who haven’t had a dengue infection before, you likely wouldn’t get it just for traveling to an endemic area, unless perhaps you routinely travel to an endemic area and have had dengue already. A titer test can confirm a previous dengue infection, but there is no indication to get vaccinated for travel yet.

Also, while in other countries it is available for use between 9 and 45 years, in the United States, Dengvaxia is only approved for children between 9 and 16 years of age.

More on Dengvaxia for Dengue Fever

Why Can’t You Give Blood After Getting a Vaccine?

If you are like most people, you have heard so much anti-vaccine misinformation that you figure it is safe to assume that everything these folks say isn’t true.

Yes, go research shedding

If you are a true skeptic, you will still do your research on any new claims just to make sure.

Why Can’t You Give Blood After Getting a Vaccine?

Although you may not have heard of any restrictions on donating blood after getting vaccinated before, it makes sense once you think of it.

You actually have to wait:

  • for up to 8 weeks after getting the smallpox vaccine
  • for up to 4 weeks after getting the MMR (because of the rubella component), chickenpox, and Zostavax vaccines.
  • for up to 3 weeks after getting the hepatitis B vaccine
  • for up to 2 weeks after getting the measles, mumps, oral polio, or yellow fever vaccines

If you notice that these are almost all live vaccines, it becomes very easy to see why you can’t donate blood shortly after being vaccinated.

Blood donation is “Acceptable if you were vaccinated for influenza, tetanus or meningitis, providing you are symptom-free and fever-free. Includes the Tdap vaccine. Acceptable if you received an HPV Vaccine (example, Gardasil).”

American Red Cross Eligibility Criteria: Alphabetical

Live vaccines can create a temporary viremia (virus particles in the blood), which could then be transferred to someone else in donated blood.

Could you get an infection this way?

Probably not.

Remember, you would only be getting the attenuated or weakened vaccine virus strain and even then, it would be a very small amount. If the person getting the vaccine doesn’t get sick from getting the vaccine, why would someone who was getting a much smaller dose through a blood donation.

Still, there is a theoretical risk, especially if the person who received the blood donation had an immunodeficiency, so people aren’t supposed to donate blood shortly after getting these vaccines.

But what about the hepatitis B vaccine. It isn’t a live virus vaccine.

The risk with this vaccine is that a very recently vaccinated donor might test positive for HBsAg (this only happens temporarily), leading the donation center to actually think that they had a hepatitis B infection, disqualifying them from ever donating blood again.

Does any of this mean that vaccines aren’t safe?

Of course not!

Just consider some of the other restrictions on donating blood:

  • You are not eligible to ever donate if you ever tested positive for hepatitis B, even if you were never sick.
  • You must wait 12 months after your last contact if you were exposed to someone with hepatitis B and you want to donate blood.
  • If you are unvaccinated, you must wait at least 4 weeks after being exposed to someone with measles.

So yes, that means that you will be much more likely to be eligible to donate blood if you are fully vaccinated and protected.

More on Donating Blood After Getting Vaccinated