Tag: BCG vaccine

What Are the Non-Specific Effects of Vaccinations?

Most of us are well aware of the risks (small) and benefits (big) of vaccines. That’s why we vaccinate our kids!

You probably aren’t aware that vaccines can also have non-specific effects.

What Are the Non-Specific Effects of Vaccinations?

Not getting measles after getting an MMR vaccine is a direct or specific effect of the vaccine.

“Vaccines are developed to produce an immune response to protect against specific disease targets. In addition to the specific effect of vaccines in reducing illness and death due to the disease targeted by the vaccine, some researchers have argued that there are additional “off-target” or “non-specific effects” (NSE) of vaccines, based on findings from observational studies. This refers to the potential effects besides the direct protection against the disease for which a given vaccine was developed.

In other words, NSE refers to any effect of a given vaccine, other than the intended effect of preventing disease caused by the specific pathogen they were designed to protect against. If present for a vaccine, NSE could potentially be beneficial, e.g. increasing protection against non-targeted infections, or disadvantageous, e.g. by increasing susceptibility to non-targeted infections.”

Non-specific effects of vaccines: Questions and answers

Not dying of another disease because you didn’t get measles would be a non-specific effect of the MMR vaccine.

It is also thought that the BCG vaccine might have a non-specific effect that protects you against other infections.

Are these non-specific effects real?

What about the studies that found the DPT vaccine could increase mortality from other infections?

Non-specific effects aren’t all positive…

The initial research on these non-specific effects of vaccines was done by Peter Aaby in Guinea-Bissau West Africa.

“A study in Guinea-Bissau published in the British Medical Journal in December 2000 suggested a nonspecific effect of routine vaccination that might influence survival in infants, either negatively or positively, depending upon the vaccine. Increased mortality was reported in children vaccinated with DPT in the 6 months following vaccination. Female gender was suggested as a modifier of the outcome.

GACVS reviewed this issue and urged WHO to arrange for testing of the hypothesis on different data sets from different countries where vaccination data, death, and other factors possibly influencing mortality had been recorded. Following an open call for proposals, WHO funded or cofunded studies in Bangladesh, Burkina Faso, Indonesia, and Papua New Guinea.

Analysis of those studies was completed: all of them showed reduced mortality in the children vaccinated with all of the vaccines. In particular, the studies showed no negative effect of DPT vaccination and no difference between males and females. Preliminary results of an independent analysis conducted to test the hypothesis on another six data sets have been communicated to GACVS. None of these confirmed the observations from Guinea-Bissau with respect to the DPT vaccine.

GACVS concluded that the evidence is sufficient to reject the hypothesis for an increased nonspecific mortality following vaccination.”

Potential adverse impact of routine vaccination

The Global Advisory Committee on Vaccine Safety of the WHO thoroughly looked into Aaby’s hypothesis.

It was rejected after further studies were done.

“The Global Advisory Committee on Vaccine Safety of the WHO, an independent group of experts in drug safety, vaccine science, and epidemiology that advises the Department of Vaccines and Biologicals of the organisation, has closely considered the reported findings and conclusions of the paper. It has found that numerous and serious deficiencies in the paper did not allow it to reach the same definitive conclusions reached by the authors. In particular, it found that the reported observations are incomplete and do not tally, no systematic effort has been made to address the likelihood of bias introduced by the method of data collection, and categorical inferences have been drawn from data that are either not significant or critically dependent on a very small number of results that might equally be explained by chance. In addition, the probability of the results being distorted by confounding factors has not been adequately addressed. The analysis was data driven and not based on a priori generation of a hypothesis, which makes interpretation of significance values and confidence limits problematic. The conclusions of this paper need to be scrutinised to the same extent as adverse events previously mistakenly attributed to diphtheria, tetanus, and pertussis vaccine.”

WHO responds to Guinea-Bissau report

And as Peter Aaby continues to publish new reports on the effects of the DPT vaccine in Guinea-Bissau, researchers have continued to investigate any possible role these non-specific effects might have on children.

The WHO Global Advisory Committee on Vaccine Safety has been reviewing the evidence on non-specific effects of vaccines on mortality since Peter Aaby published his initial research.
The WHO Global Advisory Committee on Vaccine Safety has been reviewing the evidence on non-specific effects of vaccines on mortality since Peter Aaby published his initial research.

One of the latest, a report to the Strategic Advisory Group of Experts (SAGE) on Immunization in 2014 concluded that the “data available do not provide conclusive evidence that the current schedule results in deleterious effects on all-cause mortality in children less than five years of age.”

This is mostly because studies about non-specific effects are thought to be weak and at high risk of bias.

What does this all mean?

It means that for now, we should likely stick with making our immunization decisions based on the direct effects of vaccines, knowing that they are safe, with few risks, and huge benefits.

More on the Non-Specific Effects of Vaccinations?

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

Recognizing Old Vaccine Scars

Do you have a scar on your arm and you aren’t sure why it is there?

Having a smallpox vaccine scar makes you a part of history.
Having a smallpox vaccine scar makes you a part of history.

Is it from the smallpox vaccine?

Recognizing Old Vaccine Scars

Classically, there are two vaccines that can leave a scar – the ones that protect us against smallpox and tuberculosis.

“BCG scar is a surrogate marker of vaccination and an important index in the vaccination program.”

Dhanawade et al on Scar formation and tuberculin conversion following BCG vaccination in infants: A prospective cohort study

And there are a few easy ways to tell if you have a smallpox scar.

When were you born? Remember, the smallpox vaccine hasn’t been used in the United States since the early 1970s and its use stopped everywhere in 1986.

And where were you born?

The BCG (bacille Calmette-Guerin) vaccine, on the other hand, is still in use in many countries, and is given at birth to prevent tuberculosis disease, including meningitis and disseminated tuberculosis. It isn’t routinely used in the United States though “because of the low risk of infection with Mycobacterium tuberculosis, the variable effectiveness of the vaccine against adult pulmonary TB, and the vaccine’s potential interference with tuberculin skin test reactivity.”

Do you have a vaccine scar on your arm?
Do you have a vaccine scar on your arm? Photo by Earl Hershfield

In general though:

  • the BCG vaccine scar has a raised center
  • the smallpox vaccine scar is depressed, with lines that radiate to the edges

Complicating matters is the fact that you can have multiple scars from each vaccine…

“In 1972, the National Advisory Committee on Immunization in Canada recommended that routine immunization of infants for smallpox be stopped. Very few Canadians born after 1972 have been immunized against smallpox. Those, like me, who were immunized prior to that date have little or no immunity left. Nothing, but a small scar as testimony to a grand global achievement.”

Diane Kelsall on A Small Scar

Do you have any vaccine scars?

More on Recognizing Old Vaccine Scars

Why Isn’t There a Vaccine for Leprosy?

Why do anti-vaccine folks talk about leprosy (Hansen’s disease) so much?

“LEPROSY. I’m curious why there isn’t a vaccine for leprosy. With all the other bazillion vaccines out there, why not one for leprosy?”

We don’t have anywhere near a bazillion vaccines, but did you know that there actually is a vaccine for leprosy?

“Why aren’t you walking around concerned about leprosy every day? Why aren’t you concerned about someone from another country bringing leprosy into Australia or the US and somehow exposing all of our most vulnerable to this illness? I’ll tell you why. Because there’s no vaccine for leprosy. You are afraid of what we vaccinate for because these illnesses are hyped up all of the time. It’s propaganda. ”

Learn the Risk – Why aren’t we afraid of all diseases?

Don’t expect the leprosy vaccine to be added to our immunization schedule any time soon or to increase your fears about leprosy, as leprosy is not highly contagious and it can be treated, and even cured.

And while there are about 150 to 250 cases in the United States each year, most are in folks who used to live in areas of the world where leprosy is more common. Unlike measles, you aren’t likely to get leprosy at school or daycare or going to Disneyland, although you could get it if you have a pet armadillo.

Leprosy Vaccines

A vaccine against leprosy is important though. As with other diseases, we are seeing multi-drug resistant forms of Mycobacterium leprae, the bacteria that causes leprosy.

The new leprosy vaccine that is being developed will hopefully help to finally eliminate leprosy in parts of the Africa, Asia and Latin America where it is still a problem.

Throughout much of the 20th Century, people with leprosy in the United States were treated at the National Leprosarium in Carville, Louisiana.
Throughout much of the 20th Century, people with leprosy in the United States were treated at the National Leprosarium in Carville, Louisiana.

But it isn’t the first leprosy vaccine that we will have had.

Various leprosy vaccines have been developed and tested since the 1980s.

Also, the M. bovis BCG vaccine has been known to provide protection against both Mycobacterium tuberculosis (tuberculosis) and the related Mycobacterium leprae (leprosy) since as early as 1939.

“BCG vaccination is recommended in countries or settings with a high incidence of TB and/or high leprosy burden.”

BCG vaccines: WHO position paper – February 2018

The new leprosy vaccine, a sub-unit vaccine, will hopefully be more effective than previous strategies though, and will work to both prevent and treat leprosy.

Another leprosy vaccine, Mycobacterium indicus pranii (MIP), is being developed and tested in India.

Still, leprosy will never be eradicated, as armadillos serve as an animal reservoir for the Mycobacterium leprae  bacteria.

What to Know About Leprosy Vaccines

At least two leprosy vaccines are being developed and tested to help eliminate leprosy from the areas of Africa, Asia and Latin America where it is still a problem.

More on Leprosy Vaccines