So-called Disclosure of Pfizer’s Vaccine Trials Are Misinterpreted
In today’s Medium article, I’ll address a false claim where individuals online have stated that the vaccine is illegal and misinterpreting information on why transmission via any vaccine trials never happens. Without further ado let’s get into the article.
➡️ The Misinterpretation of Transmission Claims
A Pfizer representative in an interview stated the trials never tested for transmission. Vaccine clinical trials for drug approval are not meant to test transmission, that comes afterwards. Clinical trials are intended to check the safety and efficacy of new drugs and vaccines before they are approved for widespread use.
SARS-CoV-2 vaccine trials did not directly estimate vaccine efficacy against transmission [1]. However, in a study published in the ScienceDirect journal, the authors estimate that Moderna’s vaccine reduces the potential for transmission by at least 61%.
The vaccine's ability to prevent transmission was assessed during it’s rollout, via a study published [2] in the Springer science journal. The study looked at recent evidence at that time and showed that the vaccines did prevent transmission, looking at one study where vaccines had efficacy in preventing infection of 90% 14 days after the second dose and 80% 14 days after the first dose [3].
The Association of American Medical Colleges [4] indicates that — “the clinical trials were not designed to test whether any of the trial participants contracted COVID-19 but showed no symptoms.” The reason transmission was not tested during these trials was that the trial size & duration (of trials) needed to have a larger participant pool, and a longer time period was needed for trials thus the end goal would be preventing deaths (if this had happened).
This was dated: 21/10/2020, so Pfizer never lied, clinical trials for ANY vaccine never test for transmission “None of the trials currently underway are designed to detect a reduction in any serious outcome such as hospitalisations, intensive care use, or deaths. Nor are the vaccines being studied to determine whether they can interrupt transmission of the virus,” [5]
References: [1] https://www.sciencedirect.com/science/article/pii/S0264410X21007350
[2] https://link.springer.com/article/10.1007/s10787-021-00847-2
[3] https://www.nejm.org/doi/10.1056/NEJMsr2105280
[4] https://www.aamc.org/news-insights/6-myths-about-covid-19-vaccines-debunked
[5] https://www.bmj.com/company/newsroom/covid-19-vaccine-trials-cannot-tell-us-if-they-will-save-lives/
➡️ Studies Showing Prevention of Transmission
- A study published in the prestigious NEJM science journal — “Vaccination was associated with a smaller reduction in transmission of the delta variant than of the alpha variant, and the effects of vaccination decreased over time. Data from a test cohort of 146,243 tested contacts.” [1]
- Israel data published in The Lancet — “The results support an early, significant rate-reduction in laboratory-confirmed SARS-CoV-2 infections and COVID-19, as well as decreased infectivity, manifested by the reduced prevalence of infection in those tested following exposure, and also by higher Ct value and negative antigen tests in vaccinees who did become infected.” [2]
- “Our results show evidence of a slight reduction in the infectiousness of vaccinated individuals who become infected in addition to protection against the susceptibility to infection, leading to an overall reduction in the risk of transmission.”
- A JAMA study looking at recipients who have one vaccine dose — “Even one dose of a vaccine provided protection against infection. Data for 503 875 individuals (mean [SD] age, 59.7 [14.7] years; 263 228 [52.4%] women) were analyzed, of whom 351 897 had follow-up data for days 13 to 24. Vaccine effectiveness against symptomatic COVID-19 was 54.4% (95% CI, 21.4%-73.6%).” [4]
- Even two pre-print studies have found robust evidence that Covid-19 vaccines can prevent transmission [5] [6].
Two vaccine doses provided high protection against SARS-CoV-2 infection and COVID-19-related hospitalization with the Alpha and Delta variants with protection waning over time with higher estimates after the third dose. The third vaccine dose substantially increased the protection against Delta and Omicron. PREPRINT 20th April 2022. [6] - This study is taken from over 13k Canadian long-term care residents who tested posted for Omicron, which lasted until April 2022, the study was accepted on 8th June 2022.
Conclusion to BMJ study: “The findings suggest that compared with the third dose of mRNA covid-19 vaccine, a fourth dose improved protection against infection, symptomatic infection, and severe outcomes among long-term care residents during an omicron dominant period.” [7] - In Japan where most are infection-naïve and strict prevention measures are maintained regardless of vaccination status, 2-dose mRNA vaccines provided high protection against symptomatic infection during the Delta-Dominant period and moderate protection during the Omicron-dominant period. 3rd August 2022. [8]
References: [1] https://www.nejm.org/doi/full/10.1056/nejmoa2116597
[2] https://www.thelancet.com/journals/lanepe/article/PIIS2666-7762(21)00127-7/fulltext
[3] https://www.science.org/doi/10.1126/science.abl4292
[4] https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2780700
[5] https://www.medrxiv.org/content/10.1101/2022.08.08.22278547v2.full-text
[6] https://www.medrxiv.org/content/10.1101/2022.04.20.22274061v1
[7] https://www.bmj.com/content/378/bmj-2022-071502
[8] https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciac635/6653543
➡️ META-Analysis on Covid-19 Vaccines Preventing Transmission.
- Published on 26th August 2022 and published in the Frontiers science journal — “The results of this meta-analysis indicated that vaccination against COVID-19 with BNT162b2 mRNA, mRNA-1273, and ChAdOx1, and also their combination, was associated with a favourable effectiveness against SARS-CoV2 incidence rate, hospitalization, and mortality rate in the first and second doses in different populations.” [1]
- A BMJ meta-analysis looked at three-dose regimens, published on 31st May 2022 — “Heterologous and homologous three-dose regimens work comparably well in preventing covid-19 infections, even against different variants.”
References: [1] https://www.frontiersin.org/articles/10.3389/fpubh.2022.873596/full
[2] https://www.bmj.com/content/377/bmj-2022-069989
➡️ Other Info on Vaccines
Below are the basics of how vaccines work, showing more evidence that vaccination in general prevents transmission and other information regarding vaccines with the quotes being used as supporting evidence.
- “Not all vaccines are completely effective. For example, the chickenpox vaccine is about 90% effective. This means that some people who are vaccinated might still get disease symptoms if they’re exposed to the chickenpox virus. But if this happens, people get less severe symptoms and usually recover more quickly.”
- “Being vaccinated prevents people from catching the disease in the vast majority of cases.” [2]
- “In general, most vaccines do not completely prevent infection but do prevent the infection from spreading within the body and from causing disease. Many vaccines can also prevent transmission, potentially leading to herd protection whereby unvaccinated people are protected from infection by the vaccinated people around them because they have less chance of exposure to the virus.” [3]
References: [1] https://raisingchildren.net.au/babies/health-daily-care/immunisation/vaccine-immunity-how-vaccines-prevent-infectious-diseases#how-vaccines-give-you-immunity-nav-title
[2] https://ec.europa.eu/info/live-work-travel-eu/coronavirus-response/safe-covid-19-vaccines-europeans/how-do-vaccines-work_en
[3] https://coronavirus.jhu.edu/vaccines/vaccines-faq
➡️ Conclusion
It’s very easy to go into the rabbit hole of misinformation when we hold onto specific core beliefs, in regards to the claims made about transmission and vaccine trials, vaccine clinical trials were never made to estimate the efficacy of transmission, so the claims are based on unfounded misunderstandings driven by uninformed people. Do Covid-19 related vaccines prevent transmission? Yes
💥 Thanks for reading, Lawrence. Please consider a small contribution, in the form of a beer as all articles are created in my small amount of spare time: https://www.buymeacoffee.com/LawrenceRob