Pfizer did not need to test the vaccine for transmission prevention. This does not mean, however, that no such tests have been conducted

Pfizer did not need to test the vaccine for transmission prevention. This does not mean, however, that no such tests have been conducted

The speech of Janine Small, a representative of Pfizer, in the European Parliament about the lack of research on transmission before the introduction of vaccines on the market, was widely commented in the Internet space. The recording of her response was shared by numerous accounts as evidence of inefficiency of vaccines and of misleading citizens regarding the issue of covid passports.

However, this statement was not surprising at all – clinical trials were focused on examining the safety and efficacy profile of vaccines. Pfizer never claimed to have tested the vaccines for transmission before rolling them out, as this was not necessary to obtain a sales approval. The first publications on limiting transmission began to appear in 2021, after the start of the vaccination program.

Online posts manipulate recipients in several ways: firstly, by suggesting that COVID-19 vaccines have never been tested for transmission, and secondly, that they have never limited it. The case was previously described by Health FeedbackLead StoriesPolitiFactAP NewsFactCheck.orgReuters and Konkret24.

The testimony of Pfizer representative in the European Parliament that the effectiveness of the vaccine in limiting the transmission of SARS-CoV-2 was not tested prior to rolling it out, indicates that the covid passports were unfounded.
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Rob Roos

The narrative of sensational new evidence was initiated by Rob Roos, a member of the European Parliament from the Netherlands, who was the author of the question to Janine Small regarding the transmission. His tweet starting with the words “Breaking” gathered over 425 thousand reactions. The MEP formed an accusation that the slogan “get vaccinated for others” had always been a lie. Furthermore, in the video he claims that Janine Small’s confession deprives covid passports of a legal basis.

Rob Roos / Pfizer transmission
Source: Twitter

This information was re-shared by numerous profiles, such as KonfederacjaGrzegorz PłaczekPaweł Basiukiewicz and many others. The case was also described by Do Rzeczy, however, Rob Ross’s narrative was left without a substantive comment. The nczas portal, it a fashion that’s typical in their social media posts, presented the information as a sensational discovery:

Pfizer representative’s SHOCKING confession. “It turned out to be a cheap lie” [VIDEO]
A video of the Dutch entrepreneur and MEP Rob Roos with almost 9 million views on Twitter. He revealed the truth about Pfizer’s jab.

Due to the lack of research on transmission, Grzegorz Braun described vaccination as quackery and asked a rhetorical question: “And who is the conspiracy theorist now?”. His post was shared on his profile and on the profile of Konfederacja Korony Polski and had a total of 90 thousand views. It was also shared on Telegram.

Grzegorz Braun / Pfizer transmission
Source: Facebook
Konfederacja Korony Polskiej / Pfizer transmission
Source: Facebook

During the conference, Sławomir Mentzen stated that “it was supposed to block the transmission of the virus, but didn’t”, and then he elaborated on how the foundations of science and the scientific method are being deviated from nowadays. Meanwhile, contrary to Mentzen’s words, studies published in 2021 showed that COVID-19 vaccines did limit the transmission of SARS-CoV-2.

This topic was raised on 16 October by Bogdan Rymanowski, a Polsat reporter in his show Śniadanie Rymanowskiego. Among the 7 guests invited to speak on this subject, he appointed a member of Konfederacja, Jakub Kulesza, to comment on this. All we could learn from his answer is that “society is being lied to”, “politicians make cynical use of the omnipresent fear”, and that he avoids answering a question about his vaccination status.

While it would be advisable to raise this topic among experts who could provide substantive explanations of the discussed issue, raising it among a group of politicians is a counterproductive action that adds fuel to the already heated debate, polarises the audience, and brings benefits only in the form of more views.

Bogdan Rymanowski was not the only Polsat reporter who fitted right into the narrative of the anti-vaccine environment. Three days earlier, Wojciech Dąbrowski published a tweet in which he considered the grounds of the legitimacy of covid passports fake news:

Wojciech Dąbrowski / Pfizer transmission
Source: Twitter

Searching for a scapegoat

People sharing this supposedly sensational discovery claim that citizens have been deceived by those who say that vaccination limits transmission. However, specific names of people who allegedly claimed that Pfizer had tested this before the vaccine was rolled out, were rarely mentioned.

In an attempt to discredit Prof. Krzysztof Pyrć, one Internet user published a screenshot of an interview in which the biologist talked about the research on limiting transmission – however, the article appeared in June 2021, i.e. half a year after the start of the vaccination program, when results on this subject were already available (we described it in May 2021 and in September 2021).

Krzysztof Pyrć

źródło: Twitter

Did Pfizer have an obligation to test the vaccines for transmission?

No, these studies were not required by the European Medicines Agency (EMA) as part of the sales authorisation process for COVID-19 vaccines. The deliverables of phase III of clinical trials were the prevention of symptomatic COVID-19 infection and severe disease symptoms.

In December 2020, EMA published a presentation in which the prevention of symptomatic infection was listed under the assessment of the benefits provided by the vaccine. On the same slide, we can also read about other benefits “probably unknown at the time of approval, which would be determined during its application”:

– long-term protection
– infection prevention (asymptomatic cases)
– prevention of virus transmission in the community – requires specific tests after approval

In addition, in another document published in the same month, EMA states that the impact of vaccination with Comirnaty product on transmission of the SARS-CoV-2 virus in the community is not yet known.

Research on the impact of vaccination on the transmission of SARS-CoV-2 was not a requirement of the US Food and Drug Administration (FDA) either. In a statement published in December 2020, FDA clarified that there is currently no data available to make a determination about how long the vaccine will provide protection, nor is there evidence that it prevents transmission of SARS-CoV-2 from person to person.

Moreover, contrary to what may be suggested by the narratives produced by the anti-vaccine environment, Pfizer has never claimed to have investigated the efficiency of vaccines in limiting the transmission of SARS-CoV-2 between humans before the vaccine was authorised for sale.

“Unjustified covid passports”

It is often argued that in the absence of research on the transmission, covid passports were unfounded. However, these people ignore the fact that the decisions to introduce the passports were made in Poland in June 2021, when research confirming the limitation of SARS-CoV-2 transmission as a result of vaccination were already available.

As emphasised by Prof. Krzysztof Pyrć in his post on Twitter, at the beginning it was not known to what extent vaccines reduce transmission, therefore the vaccination program was available in the first place for people from groups with the highest risk of severe symptoms. Over time, however, it turned out that the vaccines did reduce transmission, and the data served as the grounds for the introduction of covid passports.

In his comment for Konkret24, Prof. Krzysztof Pyrć points out that:

Along with the emergence of new variants, vaccine effectiveness in preventing transmission and infection itself decreased, and in case of omicron it is close to zero in this aspect. What is important, however, is that the effectiveness of the original vaccines in preventing severe symptoms and death remains very good. New, updated vaccines are supposed to restore the transmission reduction, but at this time, we are still waiting for results.

Moreover, Prof. Agnieszka Szuster-Ciesielska points out to the correlation between milder symptoms of COVID-19 among those vaccinated and a shortened transmission time of the virus:

Even if a vaccinated person is infected, the replication of SARS-CoV-2 will be shorter, and thus the transmission time of the virus will also be significantly shortened. There are a number of works showing the shortened time of spreading the coronavirus by vaccinated people compared to non-vaccinated ones, e.g.…/10.1101/2021.07.28.21261295v1…/jamanetwo…/fullarticle/2792598

“Get vaccinated for others”

When referring to the slogan that Rob Roos described as a lie, additional context should be considered. At the time of the first vaccination campaigns, health care facilities were struggling with shortages of doctors, extreme fatigue of staff, and inefficiency of hospitals due to a large numbers of COVID-19 patients. Subsequent wards were transformed into covid wards, and doctors of various specialisations were delegated to work there. This in turn caused difficulties in accessing medical care for patients with other diseases. Surgeries were postponed because there was a lack of, among others, anaesthesiologists who were looking after patients with severe symptoms of COVID-19 at that time.

The introduction of common vaccinations, whose effectiveness in alleviating the symptoms of the disease and reducing mortality due to COVID-19 was already documented at that time, was to relieve the burden on health care facilities and thus facilitate access for patients not only with COVID-19. Lockdowns were introduced in order to limit the transmission and relieve the burden on medical facilities, which until now have been considered unjustified by the anti-vaccine circles.


The news shared by the anti-vaccine community is neither new nor ground-breaking. Clinical trials of vaccines prior to sales authorisation were not designed to evaluate the limitation of viral transmission. The deliverables of these studies were the assessment of the effectiveness of preventing symptomatic disease and severe symptoms of COVID-19. Also, Pfizer did not claim to have conducted human studies on SARS-CoV-2 transmission prior to approval.

The studies, which were published already after the introduction of vaccines on the market, confirmed their effectiveness in limiting transmission, and on this basis the decision to introduce covid passports was made in June 2021.

Due to the above, presenting Janine Small’s testimony as a breakthrough information, “admitting to a lie” or evidence of the groundlessness of covid passports means either that those pushing these narratives are not familiar with the subject matter, or that they intentionally generate sensation in order to increase views and mislead the audience.


Założyciel, twórca i fundator Fundacji "Przeciwdziałamy Dezinformacji". Zawodowo zajmuje się bezpieczeństwem w internecie i programowaniem. Prywatnie społecznik, pasjonat internetu. Wieloletni wolontariusz Fundacji "Dom w Łodzi". Wolontariusz roku 2015 województwa łódzkiego. Jeden z laureatów Barw Wolontariatu w 2015 roku. Email: kontakt(at)