COVID-19 Vaccine Efficacy

The efficacy of COVID-19 vaccines can be viewed in multiple ways. These include metrics of infectivity, transmission, symptomatic disease, disease severity, hospitalization, death, and others. The most common ways are to view efficacies individual COVID-19 vaccines or COVID-19 vaccination programs as a whole. Many nations have used multiple vaccines both nationally and with individuals, which makes teasing apart individual data extremely problematic. However, observations on overall efficacy of national and international aggregate vaccination campaigns can still be revealing.

Discussions of Mechanism

Pathologist Ryan Cole points out that the vaccinated still carry high viral loads of SARS-CoV-2 because the vaccines do not cause secretion of IgA antibodies and that the T cell infiltrates are tissue destructive.1) Dr. Sucharit Bhakdi and Dr. Arne Burkhardt concur, stating that the current COVID-19 vaccines elicit IgM antibodies and circulating IgA antibodies, but not the secretory IgA antibodies needed to protect the mucous membranes that line the respiratory and intestinal tract.2)

Research on COVID-19 Vaccine Efficacy

There are several forms of evidence with regard to vaccine efficacy, of which reports from trials and observational studies. It is worth noting that the trial reports are self-reported by the vaccine manufacturers with little outside oversight.

Evidence from both trial reports and retrospective analysis show similar results of increased infection and transmission among the recently vaccinated, though published efficacy computations seem to generally exclude these infections from efficacy computations. Including them dramatically changes efficacy results.3)

COVID-19 Vaccine Trials

The first evidence for the efficacy of COVID-19 vaccines came from self-reported trials conducted by Pfizer and Moderna. These trials reported highly similar efficacy results for their mRNA vaccines. However, these trials are fraught with data exclusions, whistleblowers, and secrecy that has resulted in tense court battles.

See more complete details at COVID-19 Vaccine Trials.

Retrospective Analyses

  • April 15, 2021 - A retrospective analysis on Israel claims to show extremely high Pfizer vaccine efficacy rates from low to high 90s (percentages) for essentially all tested endpoints.4)
  • May 5, 2021 - Another retrospective analysis on Israeli claims to show extremely high Pfizer vaccine efficacy rates.5)
    • There is a substantial conflict of interest as at least 8 of the authors admit to holding Pfizer stock and stock options.
    • The authors inexplicably failed to make an expected standard risk-adjustment in their calculations, inflating efficacy results.6)
  • Sep 28, 2021 - Waning of IgG, Total and Neutralizing Antibodies 6 Months Post-Vaccination with BNT162b2 in Healthcare Workers7)
  • Nov 18, 2021 - Isolation of 4000 SARS-CoV-2 shows that contagiousness is associated with viral load, not vaccine or symptomatic status8)
  • June 23, 2022 - Comparative effectiveness and durability of COVID‐19 vaccination against death and severe disease in an ongoing nationwide mass vaccination campaign9)
    • The lead author and a co-authored also authored a paper in support of lockdowns. That co-author is a spokesman with a spokesman for the Hellenic Ministry of Health.10)
    • The waning of VE from 90% to 80% is substantially less than from other reported retrospective results.
    • Says the olderly are more than 1000x as at risk as the young without even a word suggesting that absolute benefits may not justify the risks for the young.

Surveillance Data

Global COVID-19 Vaccine Systemic Efficacy Statistics

* Mathew Crawford wrote at Rounding the Earth about how COVID-19 cases and deaths are going up in far more nations than in where they are going down since vaccine rollout. (Systemic COVID-19 Vaccine Efficacy Basics) The article reports that as of October 20, 2021, according to the Our World in Data COVID-19 dataset,

  • Cases have increased 26.1% in Africa.
  • Cases have increased 169.6% in Asia.
  • Cases have increased 690% in Australia.
  • Cases have increased 56.6% in Europe.
  • Cases have increased 67.6% in North America.
  • Cases have increased 59.9% in South America.
  • Cases have increased 76.3% worldwide.
  • Deaths have increased 27.1% in Africa.
  • Deaths have increased 122.8% in Asia.
  • Deaths have increased 155.3% in Australia
  • Deaths have increased 30.2% in Europe.
  • Deaths have increased 37.3% in North America.
  • Deaths have increased 55.7% in South America.
  • Deaths have increased 46.3% worldwide.

* Mathew Crawford wrote at Rounding the Earth about how there is no distinction in any COVID-19 vaccine trials data or subsequent retrospective analyses that is inconsistent with the hypothesis that the vaccines are ineffective. (Systemic Vaccine Efficacy, Part 4)

Selective Reporting

In February, 2022, the CDC admitted to withholding critical data on boosters, hospitalizations, and wastewater analyses.11)

Local Observational Studies and Anecdotes

Little difference in SARS-CoV-2 positive rates was observed among airport travelers in Israel. 12)

Despite a 99.5% double-vaccination rate, Co Waterford, Ireland had the highest case rate in all of Ireland in early November, 2021.13)

More recently, Rintrah wrote on the vaccine lack of effectiveness in Denmark:

Efficacy Specific to Those Recovered From COVID-19

  • Effectiveness of the BNT162b2 Vaccine after Recovery from Covid-1914)

Booster Efficacy

One group of researchers published a claim of 92% to 95% efficacy against COVID-19 among boosted Israelis.15)

Waning Efficacy

In late 2021, a story of waning efficacy begin to appear, seemingly bolstered by several published papers.16)

There has been no effort to distinguish waning efficacy from statistical sieves.

Waning Booster Efficacy

Medpage Today reported that COVID vaccine booster efficacy may wane quickly.17)

Efficacy by Variant

According to Peter McCullough, the data from the UK Covid briefing of December 21, 2021,18) “shows that the most effective product against Delta and the legacy strains is now near zero efficacy over time against the milder and more brief Omicron strain.”

Efficacy vs. Delta

  • Aug 12, 2021 - Bernal et al: Effectiveness of Covid-19 Vaccines against the B.1.617.2 (Delta) Variant 19)
  • June 23, 2022 - Comparative effectiveness and durability of COVID‐19 vaccination against death and severe disease in an ongoing nationwide mass vaccination campaign20)
    • This study from Greece concludes 90% VE which waves to 80% over six months, consistent over age bands.

Efficacy vs. Omicron

There are many reports and studies suggesting that the vaccines have a negative efficacy rate with respect to one or more of the SARS-omicron viruses.21)

Critiques of Data

Martin Neil et al wrote up a statistical analysis (in preprint as of December 14, 2021) suggestive of systematic mis-categorization of vaccination status making COVID-19 vaccine efficacy appear better than reality in retrospective analyses.

Professor Norman Fenton and colleagues noted numerous statistical sieves and paradoxes that make published studies unreliable.22) In a blog post, Fenton demonstrated that in a simulation, either delays in death reports or the counting of recently vaccinated as unvaccinated can fully explain claimed efficacy rates.23)

Pharmaceutical marketing expert, biotech analyst, and former Pfizer employee Karen Kingston argues that infections rose substantially after injection with COVID-19 vaccines.24)

The Canadian Covid Care Alliance published a critique of the safety and efficacy demonstrated in Pfizer's 6-month trial data published in the New England Journal of Medicine on January 10, 2022.25) 26)

Efficacy Against Non-COVID-19 Mortality

Strangely, multiple research publications purport to show COVID-19 vaccines broadly reducing non-COVID-19 risk of mortality. The extremely unlikeliness of such results point to the hypothesis that data definitions and statistical sorting is behind most or all of the efficacy reported in some trials and studies.27)28)29)

Efficacy Against Non-COVID-19 Hospitalization

In a retrospective analysis of New York state hospitals, researchers claim to see no real declining efficacy at preventing hospitalization from the various COVID-19 vaccines as the delta strain became predominant.30)

Examination of All-Cause Mortality Risk

  • Columbia University research Spiro Pantazatos and colleague Herve Seligmann produced a study showing an association between greater COVID-19 vaccination and higher all-cause mortality.
  • Age adjusted all cause mortality trends 2000-2021 in Europe. An extremely detailed Substack piece from Orwell2024. Among the many conclusions are; 1) 2020: The age adjusted mortality demonstrates the overreaction in the Covid-19 crises; 2) 2021: Neither a positive nor negative impact of the vaccine can be seen; and 3) The observed excess mortality in Austria and Netherlands is dominated by mortality in the elderly age bins. Those are 95% vaccinated like in Sweden, Spain and France. The vaccine doesn’t reduce nor increase all cause mortality. It isn’t the underlying root cause. QR passports and the one dimensional panic driven C19 health focus has to stop.

Data Controversies

Official efficacy calculations often skip the first 10, 12, 14, or 21 days before computing efficacy. But those days cannot be skipped in a risk-benefit analysis (or in real life), and what happens during that span could be dangerous.31)

COVID-19 vaccine data discussions have been made confusing if not outright fraudulent by the unclarified or misclarified use of data categories such as intervals “first 14 days after dose 1”. It is unclear the extent to which such categorization has been used, intentionally or otherwise, to rig vaccine efficacy statistics, but the effect is undisputably large when such miscategorization takes place.

  • Jan 13, 2022 - Data analyst Joel Smalley caught the government of Alberta red-handed dumping half of the COVID-19 deaths of those vaccinated into the unvaccinated pool which had the effect of resersing negative vaccine efficacy.32)

Correlation Analysis

  • Harvard University researcher S.V. Subramanian and colleague Akhil Kumar published a correlation study in the European Journal of Epidemiology show positive correlation between COVID-19 vaccinations and COVID-19 cases worlwide (a broad subset of 68 nations), and essentially zero relationship in the United States. (study)
  • Mathew Crawford wrote at Rounding the Earth about the positive global correlation between COVID-19 vaccinations and COVID-19 cases and deaths among all nations. (Systemic COVID-19 Vaccine Efficacy, Part 2)
  • Nov 3, 2021 The Expose: A Deadly Pandemic of the Fully Vaccinated – Worldwide data from 185 nations proves the highest Covid-19 Death rates are in the most vaccinated countries
  • Mathew Crawford wrote at Rounding the Earth about the positive global correlation between COVID-19 vaccinations and COVID-19 cases and deaths among all nations over numerous time periods. (Systemic COVID-19 Vaccine Efficacy, Part 3)
  • “Increases in COVID-19 are unrelated to levels of vaccination across 68 countries and 2947 counties in the United States” by Subramanian & Kumar appears on PubMed Central dated September 2021. The Findings section begins, “At the country-level, there appears to be no discernable relationship between percentage of population fully vaccinated and new COVID-19 cases in the last 7 days. In fact, the trend line suggests a marginally positive association such that countries with higher percentage of population fully vaccinated have higher COVID-19 cases per 1 million people. Notably, Israel with over 60% of their population fully vaccinated had the highest COVID-19 cases per 1 million people in the last 7 days.”
  • A letter in The Lancet from November, 2021, suggests, among many other startling statistics, that “Recent data […] indicate that the epidemiological relevance of COVID-19 vaccinated individuals is increasing. In the UK it was described that secondary attack rates among household contacts exposed to fully vaccinated index cases was similar to household contacts exposed to unvaccinated index cases (25% for vaccinated vs 23% for unvaccinated).

Efficacy Among Key Subgroups

Immunosuppressed Patients

  • Nov, 2021 - A study on 133 participants including 53 immunocompetent participants show that patients with chronic inflammatory disease (CID) produced two-thirds less antibodies after vaccination.33)

Vaccine Efficacy Vs. Natural Immunity


Negative Efficacy

Fading Efficacy

Other HUGE list of links here under three headings:

  • Early COVID Treatment Works
  • Vaccinating Children Means Unnecessary Risks
  • COVID-Recovered Immunity is Durable
Dec 28, 2021 | Steve Kirsch | Bhakdi/Burkhardt pathology results show 93% of people who died after being vaccinated were killed by the vaccine |
September 28, 2021 | Jean-Louis Bayart et al | Waning of IgG, Total and Neutralizing Antibodies 6 Months Post-Vaccination with BNT162b2 in Healthcare Workers |
November 18, 2021 | Celine Boschi et al | Emerging Microbes and Infections | Isolation of 4000 SARS-CoV-2 shows that contagiousness is associated with viral load, not vaccine or symptomatic status |
9) , 20)
June 23, 2022 | Theodore Lytras et al | J Med Virol | Comparative effectiveness and durability of COVID‐19 vaccination against death and severe disease in an ongoing nationwide mass vaccination campaign | doi: 10.1002/jmv.27934
February, 2021 | Theodore Lytras and Sotirios Tsiodra | Scand J Public Health | Lockdowns and the COVID-19 pandemic: What is the endgame? | DOI: 10.1177/1403494820961293
March 31, 2022 | Ariel Hammerman et al | NEJM | Effectiveness of the BNT162b2 Vaccine after Recovery from Covid-19 | DOI: 10.1056/NEJMoa2119497
October 7, 2021 | Yinon M. Bar-On et al | JAMA | DOI: 10.1056/NEJMoa2114255
December 31, 2021 | The National Pulse | Vaccinated 21 Times More Likely to Get Omicron
September, 2021 | Norman Fenton et al | preprint | Paradoxes in the reporting of Covid19 vaccine effectiveness: Why current studies (for or against vaccination) cannot be trusted and what we can do about it |DOI:10.13140/RG.2.2.32655.30886
Scientific Review: CCCA Critique – Thomas COVID-19 Vaccines 6 months NEJM. Canadian Covid Care Alliance. Retrieved January 16, 2022, from
Bridle, B. W., Mallard, B. A., Karrow, N. A., Speicher, D. J., Chaufan, C., Northey, J. G. B., Pelech, S., Shaw, C. A., Halgas, O., McLeod, D., & Martins, I. (2022). Concerns regarding the efficacy and safety for BNT162b2 mRNA coronavirus disease (COVID-19) vaccine through six months. Canadian Covid Care Alliance.
November, 2021 | Deepak et al | Annals of Internal Medicine |
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