15,000 lives per quarter: how the phrase “that’s just your opinion” killed during the pandemic

The article analyzes the impact of disinformation about mRNA vaccines during the COVID-19 pandemic in the Czech Republic. It shows how the strategy “that’s just your opinion”

mRNA. Four letters that in 2021 became the most dangerous word in the Czech internet jungle.

Messenger ribonucleic acid — a molecule that enters a cell, delivers instructions to manufacture a harmless fragment of a viral protein, and within a few hours breaks down. It never enters the cell nucleus. It cannot alter DNA. Research into mRNA vaccines had been underway since the 1990s, with the first human clinical trials — against rabies — beginning in 2013.

But on social media, reality looked different. mRNA vaccines supposedly altered human DNA and created "genetically modified humans." They contained microchips, graphene oxide, substances from aborted fetuses. They caused infertility, cancer, AIDS. On one Czech disinformation server it was claimed that mRNA vaccines contain a spike protein that is poisonous — and that the only defense is ivermectin, an antiparasitic preparation intended for horses. Or horseradish. Or mustard. No, this is not a parody. Thousands of people believed it.

And then they made their decision. Not for the needle. For "their own opinion."

In the summer of 2021, every adult in Czechia had access to a vaccine free of charge. Vaccination centers had spare capacity. Even so, by the end of the campaign only 64.4% of the population had been fully vaccinated — fewer than 6.9 million people. Vaccination coverage among adults (aged 16 and over) reached roughly 74%, slightly above the European Union average. The EU met its target of 70% of adults vaccinated in August 2021. Yet more than a third of Czechia's entire population — including children, for whom the vaccine was not available at the time — remained entirely unprotected.

At the same time, a second offer was circulating online: the Russian Sputnik V, presented by the disinformation scene as an "mRNA-free alternative," as proof that the West was concealing a safe solution. Slovakia purchased Sputnik V; in Czechia it remained a subject of speculation. But its main role in the information space was not to cure — it was to undermine trust in mRNA technology. The message was clear: you see, other options exist, but "they" won't let you have them. Now why might that be?

This strategy did not require that people actually receive Sputnik. It was enough that they began to doubt the Pfizer and Moderna vaccines. And that succeeded.

Beneath discussions about vaccines, variations on a single sentence kept recurring: "That mRNA vaccines work is just your opinion. We have a different opinion."

As if it were a matter of taste. As if a claim about a vaccine's effectiveness belonged in the same category as the question of whether red or blue is prettier.

In 2016, Oxford Dictionaries chose "post-truth" as its word of the year — a state in which verifiable facts have less influence on public opinion than appeals to emotion and personal conviction. The COVID-19 pandemic turned this diagnosis from an academic abstraction into a mass experience — and into a measurable catastrophe.

To understand why "everything is just an opinion" kills, we have to distinguish three categories of claims.

Verifiable facts. mRNA does not enter the cell nucleus. COVID-19 vaccination reduced the risk of death — in Czechia, by a factor of 9.5 among people aged 45–64 compared with the unvaccinated. These are not opinions. These are measurement results.

Interpretations dependent on context. Were the lockdowns too strict? Should schools have closed sooner? It depends on what we measure — death tolls, economic damage, children's mental health. This is not pure fact, but neither is it pure opinion. The quality of the argument varies.

Value judgments. Is personal freedom more important than protecting society? Here values and political philosophy come into play.

Radical relativism blends these three categories together. It says: "everything is an opinion," and in doing so gives the conspiracy theory about graphene in vaccines the same weight as a controlled clinical trial with thousands of participants. This is not a philosophical position. It is an intellectual capitulation with measurable consequences.

And here come the numbers that are not an opinion.

The demographers Dagmar Dzúrová and Klára Hulíková Tesárková of the Faculty of Science, Charles University, analyzed data from the Institute of Health Information and Statistics (ÚZIS) for October to December 2021 — the period of the delta-variant wave, when practically every adult in Czechia had access to a vaccine. The results:

The risk of death from COVID-19 among the unvaccinated compared with the fully vaccinated in the same age group was 9.5× higher at ages 45–64, 7.3× higher at ages 65–84, and 6.4× higher among people over 85.

Over these three months, thousands of people died of COVID in Czechia. The unvaccinated made up a clear majority of the victims — even though they were a minority of the population. Dzúrová and Hulíková Tesárková estimated that in this single quarter vaccination saved roughly 15,000 lives.

Fifteen thousand people in three months.

In the United States it could be calculated more precisely. A study by Harvard and federal epidemiologists (Jia et al., European Journal of Epidemiology, 2023) estimated that between May 2021 and September 2022, 232,000 adults died needlessly because they were unvaccinated. An analysis by the Peterson-Kaiser Family Foundation arrived at a similar figure: 234,000 preventable deaths — 60% of all adult COVID deaths after vaccines became available.

Sixty percent. Three out of five of the dead need not have died.

The "it's just an opinion" strategy is not new. In the 1960s and 1970s, the tobacco industry systematically funded research designed to cast doubt on the link between smoking and cancer. A 1969 internal Brown & Williamson memo formulated the strategy openly: "Doubt is our product." There was no need to prove that cigarettes were safe. It was enough to repeat: scientists disagree.

Historians of science have documented the identical strategy in the case of climate change — delaying regulation by decades.

With mRNA vaccines it worked the same way. There was no need to prove the vaccines were dangerous. It was enough to sow doubt. A study in the journal PLoS ONE (2021), which mapped 578 disinformation claims about COVID vaccines, found that the most widespread fabrication was precisely the one about altering DNA via mRNA. According to an analysis in the Journal of Medical Internet Research, false statements by public figures made up roughly 20% of all disinformation — but generated 69% of the total reach on social media.

And then came Sputnik V — not as a vaccine, but as a narrative. As proof that "Western" mRNA technology was not the only path. That "they" were hiding something from you. That you had the right to "your own opinion." The disinformation interplay did not need people to actually receive Sputnik — it needed them to stop trusting the Pfizer and Moderna vaccines.

In Iran, from late February 2020, a superstition spread that drinking alcohol cured the disease caused by the coronavirus. People bought smuggled spirits on the black market — dealers decolorized industrial methanol with bleach. By April 2020, over 700 people had died, more than 5,000 had been poisoned, and nearly a hundred had lost their sight.

In the United States, a study by the National Bureau of Economic Research demonstrated a measurable relationship: areas exposed to television broadcasting that downplayed the pandemic showed higher numbers of both infections and deaths.

The World Health Organization coined the term "infodemic" for the spread of health disinformation. Never in history has a lie had such low costs of dissemination — and never before has it carried such a high price in human lives.

It would be convenient to tell the story in black and white. The reality is more complicated.

Legitimate skepticism is not the same as relativism. Science errs and corrects itself — that is its strength. A key study on ivermectin passed peer review and was nonetheless a fraud built on falsified data. mRNA technology genuinely was new and unfamiliar to most people. But acknowledging uncertainty does not mean asserting that "everything is an opinion." It means that truth is something we approach gradually — not something that does not exist.

"Scientific truth" can be abused. Lysenkoist biology in the USSR, "scientific racism" in Nazi Germany. The social epistemologist Jayson Harsin points out that the core of the "post-truth" problem does not lie in people ceasing to care about truth — on the contrary, they are obsessed with it. The problem is the systematic undermining of trust. But the defense does not lie in rejecting truth — it lies in open institutions that allow truth to be challenged with evidence, not with "opinions."

Those who refused the vaccine did not always have bad intentions. State institutions sent contradictory signals: they authorized unproven drugs, changed the rules, communicated chaotically. When the state loses credibility, the space for relativism expands. This is an understandable reaction — but not a correct one. Because the virus does not care what you believe.

One more argument remains — a philosophical one, but important.

The claim "there is no truth, only opinions" is self-refuting. If it is true, then it too is merely an opinion — and has no claim to greater validity than the opposite assertion. Both answers lead to a dead end.

This is not an academic trick. It is a diagnostic tool: radical relativism is not an intellectually coherent position. It is a rhetorical weapon that masquerades as philosophy.

The demographers Dzúrová and Hulíková Tesárková estimated that in a single quarter — October to December 2021 — vaccination saved roughly 15,000 lives in Czechia. Fifteen thousand people who are alive because they accepted the needle instead of an "opinion." Fifteen thousand families who did not have to call the crematorium.

During the pandemic, Czechia lost more than 43,000 lives. We do not know the exact number of those who died because of mRNA disinformation, and we probably never will. But the ÚZIS data speak clearly: the unvaccinated died many times more often — fivefold, sevenfold, nearly tenfold depending on age. And every one of them had access to a vaccine free of charge.

Meanwhile, the disinformation scene has moved on to other topics. The sentence "that's just your opinion" has remained — it has migrated to the war in Ukraine, to climate change, to artificial intelligence. To everything that is too complicated and too inconvenient.

There is no black-and-white choice between naive faith in scientific infallibility and radical relativism. But there is a space for critical thinking, where claims are judged by the strength of the evidence, not by who says them and how loudly.

Fifteen thousand lives saved in a single quarter is an argument that needs no quotation marks. And every needless grave is an answer to the question of whether there is a difference between a fact and an opinion.

Information cut-off date: March 2026. This article was prepared with the assistance of artificial intelligence (Art. 50 of EU Regulation 2024/1689). The data and sources were verified as of the date of processing.

Czech data — vaccination and mortality

ČSÚ (Czech Statistical Office): "COVID-19 killed 25,500 inhabitants of Czechia in 2021" (csu.gov.cz, 2022). ČSÚ / Statistika&My: "The figures during COVID were extreme" (statistikaamy.csu.gov.cz). Seznam Zprávy / Dzúrová D., Hulíková Tesárková K.: "Vaccination saved 15,000 lives in three months, expert says" (20 April 2022) — analysis of ÚZIS data for October–December 2021, risk ratios by age group; scientific publication: Scientific Reports 12, 2022, DOI: 10.1038/s41598-022-23023-0. iROZHLAS / Dušek L.: "Reports from the hospitals" (11 August 2021) — ÚZIS overviews. ÚZIS ČR (Institute of Health Information and Statistics): "COVID-19: Overview of deaths with regard to recorded vaccinations" — open data of the Czech Ministry of Health. OpenDataLab / ČVUT (Czech Technical University): ockovani.opendatalab.cz — 64.4% fully vaccinated (6.89 million people). iROZHLAS: "Highest rise in deaths in a hundred years" (2 February 2021) — a 15% increase, the highest since 1945.

Preventable deaths — international data

Jia K. M. et al.: "Estimated preventable COVID-19-associated deaths due to non-vaccination in the United States." European Journal of Epidemiology 38(11), 1125–1128 (2023) — Harvard T.H. Chan School of Public Health / CDC, estimate of 232,000 deaths. Peterson-KFF Health System Tracker: "COVID-19 mortality preventable by vaccines" (28 April 2022) — 234,000 = 60% of adult COVID deaths after vaccines became available.

Disinformation about mRNA

Islam M. S. et al.: "COVID-19 vaccine rumors and conspiracy theories: The need for cognitive inoculation." PLoS ONE 16(5), e0251605 (2021) — 578 disinformation claims, with the fabrication about altering DNA via mRNA the most widespread. Gisondi M. et al.: "A Deadly Infodemic." JMIR 24(2), e35552 (2022) — 20% of disinformation from public figures = 69% of reach. Britannica / NewsGuard: "The Top COVID-19 Vaccine Myths Spreading Online" (2021, updated 2025) — an overview of the most widespread fabrications. Wikipedia: "COVID-19 vaccine misinformation and hesitancy" — a summary overview with links to primary sources.

The infodemic and historical context

Hassanian-Moghaddam H. et al.: "Double trouble: methanol outbreak in Iran." Critical Care 24, 402 (2020) — over 700 dead from methanol poisoning. Oreskes N., Conway E.: Merchants of Doubt (Bloomsbury, 2010) — the tobacco and fossil-fuel industries. Oxford Dictionaries: Word of the Year 2016 — "post-truth" (languages.oup.com). Harsin J.: "Post-truth Politics and Epistemic Populism." Springer (2024). Alberer M. et al.: "Safety and immunogenicity of a mRNA rabies vaccine in healthy adults." Lancet 390(10101), 1511–1520 (2017) — the first human clinical trial of an mRNA vaccine against an infectious disease (2013–2016).

The estimate of 15,000 lives saved over October–December 2021 comes from the analysis by the demographers Dagmar Dzúrová and Klára Hulíková Tesárková (Faculty of Science, Charles University), published by Seznam Zprávy (20 April 2022) and in the peer-reviewed journal Scientific Reports (2022). It is based on a comparison of mortality among vaccinated and unvaccinated age groups from ÚZIS data. The total figure of 43,000+ COVID deaths covers the period up to December 2023 (ÚZIS / Czech Ministry of Health). The Jia et al. study and the Peterson-KFF analysis relate to the United States; a direct extrapolation to Czechia is not methodologically sound, which is why they are used in the text as a comparative reference. The causal relationship between disinformation and a specific number of preventable deaths cannot be precisely quantified — the article acknowledges this limitation. The claims about disinformation on Czech social media (graphene, horseradish, mustard, microchips) are documented in Deník.cz articles from the investigative series "Deník proti fake news" (2021). The estimate of 15,000 lives is the subject of expert debate — a critique of its methodological assumptions was published by the mathematician Tomáš Fürst (Palacký University Olomouc) in the journal Vesmír (2024); the study's authors responded to the critique in the same issue.

Transparency of creation

The concept, structure, and editorial line of the article are the work of the author, who prepared the content outline, set the key theses, and directed the entire creative process. Generative AI (Claude Opus 4.6, Anthropic) was used as a tool for research, fact-checking, and fleshing out the author's draft.

The author verified the key findings and approved the final version. No part of the text was published without conscious authorial oversight. The factual data were verified against the publicly available sources cited in the text.

This procedure complies with the transparency principles of EU Regulation 2024/1689 (AI Act). #poweredByAI