Pfizer COVID-19 Vaccine Associated With Increased Risk of Carditis (Heart Inflammation)

Despite low absolute risk, Pfizer/BioNTech BNT162b2 COVID-19 vaccine associated with increased risk of carditis.

Markedly increased risk in adolescents after 2nd dose may warrant refined vaccination strategies

A case-control study found that despite low absolute risk, there is an increased relative risk of carditis associated with BNT162b2 (commonly-known as Pfizer/BioNTech vaccine) vaccination. Considering the markedly increased risk in adolescents after the second dose, vaccination strategies may need to continuously consider the risk and benefits for different sub-populations, rather than taking a ‘one-size-fits-all’ approach. The findings will be published today (January 24, 2022) in Annals of Internal Medicine.

Carditis is a rare inflammation of the heart often caused by bacterial, viral, and parasitic infections. Common subtypes of carditis include myocarditis, an inflammation of the heart muscle, and pericarditis, an inflammation of the outer lining of the heart. Case reports of carditis after BNT162b2 vaccination have accrued globally. Several studies have also reported similar findings, but analytic research on the speculative association is limited.

Researchers from the University of Hong Kong studied 160 case patients (with carditis) and 1,533 control patients (without carditis) to examine the potential risk of carditis associated with vaccination with BNT162b2 or CoronaVac. Ten control patients were matched with case patients based on age, sex, and date of hospital admission.

After conducting analyses, the authors found 20 cases of carditis associated with BNT162b2 and 7 associated with CoronaVac vaccination. Patients who received BNT162b2 were 3 times more likely to experience carditis than unvaccinated patients. On the other hand, patients who received CoronaVac had a similar chance as unvaccinated patients to experience carditis.

The authors also observed that risk increase associated with BNT162b2 was predominant in males and was more likely to be seen after the second dose.

Cumulative incidence of carditis after vaccination was 0.57 per 100,000 doses of BNT162b2 and 0.31 per 100,000 doses of CoronaVac, demonstrating a very low absolute risk of carditis after vaccination.

According to the authors, none of the 20 case patients with carditis after BNT162b2 vaccination were admitted to the ICU or died within the observation period, compared with 14 of 133 unvaccinated patients admitted to the ICU and 12 deaths.

Reference: “Carditis After COVID-19 Vaccination With a Messenger RNA Vaccine and an Inactivated Virus Vaccine” by Francisco Tsz Tsun Lai, PhD, Xue Li, PhD, Kuan Peng, MHS, Lei Huang, MSc, Patrick Ip, MPH, Xinning Tong, PhD, Celine Sze Ling Chui, PhD, Eric Yuk Fai Wan, PhD, Carlos King Ho Wong, PhD, Esther Wai Yin Chan, PhD, David Chung Wah Siu, MD and Ian Chi Kei Wong, PhD, 24 January 2022, Annals of Internal Medicine.
DOI: 10.7326/M21-3700

American College of PhysiciansCardiologyCOVID-19HeartPopularPublic HealthVaccine
Comments ( 14 )
Add Comment
  • Sekar

    Very Interesting Finding.

    Vaccines are supposed to protect the Patient from the Virus, Pathogen or bacteria, causing the health problems, by increasing the ability of the human ecosystems immuune resonses.

    As immunity itself are individual dependentent, to use generic strategies to treat individuals , is a ab initio flawed strategy. However, beggars cannot be choosers in times of pandemic plaguing humanity.

    Normally Kids Immune Systems are supposed to be on the upswing during their youth. It declines with age. So, it is common sense, that they may require much lower dosage for attainig protection from Covid-19.

    The dosage of the vaccine required to fight the Virus needs to be determined careffully after large scale testing, for each group identified. One szie fits all strategies are flawed right off the starting gqte. However to protect 8 billion individuals is a difficult task.

    In the case of Covid 19, we are dealing with a Virus, which is really akin to a stealth bomber. We are still groping in the dark, as it appears to have the ablity to take out the different sub-systems of the human ecosystem, including lungs, heart etc.etc.

    The Mutations complicate the impact further as we dont know if the Variants of Concern will impact one or other organs much more, compared to the earlier variant. Nor do we know the impact on various Groups and sub-groups.

    Ideally, the best strategy in such situations is to take preventive measures and avoid getting infected. However vaccines are essential to reduce mortality.

    Cannot blame any Phamaceutical Company (includinf Pfizer) whose research scientists along with the academic community and Biontech came up with a vible vaccine (multiple choices existed and still does), based on different strategies adopted by different organisatios, to stop the spike protien from fusing with our cells.

    They did this for the world in a record time period. Also , Pfizer published the sixty step process used by it for production of its vaccine.

    If the same study is conducted with the principles of homeopathy ( Highly diluted molecules) incorporated, the actual dosage of the Pfizer vaccine required for children as a generic group to attain immunity , may be found to be much lower, than for adults who require two doses and boosters to ensure they are protected in case of infection by the Covid 19 Virus.

    Views expressed are personal and not binding on anyone.

  • Harvard MD PhD

    Earlier study shows significantly more myocarditis in young males who get COVID and are not vaccinated.

    ~450 cases of myocarditis per million COVID-19 infection in young males vs 77 cases following double vaccination with Pfizer/BioNTech or Moderna vaccine

  • Roger

    First Moderna … now Pfizer!

    Moderna was being used as the fall guy for the entire lot of new “vaccines” … but this “admission” about Pfizer has been forced because of potential litigation in future!

  • Andrew Gieseke

    This article is terrible reporting. The linked source does not lead to the research paper talked about. This information can not be confirmed. It can not be confirmed that the research paper was peer reviewed. Stop peddling garbage and misinformation on the internet.

  • Ed K

    This appears to be an abstract for the source study; including some reference would be better, to allow readers to see the detailed methodology. https://www.acpjournals.org/doi/10.7326/M21-3700 or https://doi.org/10.7326/m21-3700

    In general, though the harms from vaccines are (on average) minimal, they’re not entirely without risk; this is why we no longer vaccinate against smallpox. However, if the disease in question is circulating, the harms from the disease are much worse than the harms from the vaccine. Hong Kong is still pursing a zero covid strategy, which will make this comparison difficult there — but it can be done elsewhere.

    Regardless, having tried to engage with antivax folks often enough, I appreciated the inclusion at the end of the fact that none of the people who were vaccinated with BNT162b2 went to ICU or died (vs 12 unvaccinated children).

  • Ed K

    On review, I see the article includes the DOI reference — just not as a link.

  • Sidney

    Solution – Give us another option for our young and old, APPROVE THE NOVAVAX VACCINE as soon as it is submitted to the US for emergency use approval. We have been waiting long enough!!

  • Terry

    This study completely whitewashed the numbers. Pfizer’s own six month data had around 5 fatal cardiac arrests in around 22,000 intervention group subjects. If we model for 100,000 people that is more than 20 fatal cardiac arrests per 100,000. We can assume that the number of guinea pigs who developed Pericarditis and survived to be higher than the number that died from cardiac arrest. This study claims .57 per 100,000. Smh

  • Benjamin Smith

    Guess what has a much higher risk of carditis: COVID.

  • Will

    Compare 20 cases to 133 really that is not an comparing that’s 1 sided.

  • Ray

    Very responsible headline.
    Turns out covid is also associated with heart trouble, but to a greater degree.
    Hope you enjoy your clicks.🖕

  • Usman

    What a joke.looks like writer is anti-vac and researchers own moderna or astrozenca stocks.
    Patients with pfizer vaccines were reported three times more because more people have pfizer vaccine that any other brand.

  • Joseph Biden

    All of you are brainwashed sheep.

  • mike

    I would stay away from all vaccine.I took moderna the second one made me feel very ill n ever since i get flash pain in my heart.Before vaccine i had a check for arterys n heart.everything was fine now im having blood pressure problems with my blood pressure fluctuating.