A controversial 2024 study that some vaccine skeptics used to argue that millions of people likely died as a result of COVID vaccines has been retracted over misinformation and issues with the research. The article was originally published in BMJ Public Health in May 2024. It analyzed data from 47 Western countries and concluded that there had been more than three million excess deaths between 2020 and 2022, a statistic known as excess mortality. Excess mortality is a broad measure that compares observed deaths with the number that would have been expected under ordinary circumstances. It does not, by itself, identify the cause of any individual death. The authors did not specifically cite vaccines and lockdown measures as the reasons for those deaths, but they noted that the COVID vaccines that were deployed to save lives also appeared to be responsible for a large number of “suspected adverse events.” Those words, and the scale of the reported excess, made the study immediately valuable to critics of the official pandemic response. At the time of publication, the findings were taken by some prominent vaccine skeptics and critics of governmental pandemic responses—including several Republican lawmakers in the United States—as proof that the science and policies around COVID were flawed or even nefarious. “Overall, the journal concludes that the discussion of causes of mortality is imbalanced, lacks rigour, and includes misinformation,” the BMJ stated in the retraction notice. The notice does not necessarily mean the raw excess-mortality estimate was wrong; it specifically challenges the way the authors discussed why those deaths occurred. But because the paper had been amplified as evidence of vaccine-related mass death, the retraction marks a significant collapse of one of the most widely cited pieces of anti-vaccine evidence to emerge during the pandemic.
The results also immediately garnered skepticism in the weeks following publication. Many researchers who work with mortality data saw potential problems in the paper’s choice of countries, its handling of different reporting systems, and its emphasis on vaccine and lockdown harms despite the absence of cause-of-death information. A month after the study appeared in the journal, the BMJ began an investigation into its quality, as did the Netherlands’ Princess Máxima Center, a pediatric hospital where three of the paper’s four co-authors then worked. One of them, corresponding author and now independent researcher Saskia Mostert, testified before a U.S. congressional subcommittee about the report’s findings in June 2026. At that hearing, Mostert told lawmakers that she and her co-authors encountered “blind and irrational fury” after the paper’s publication, and she said she had resigned from the Princess Máxima Center after it opened its scientific integrity investigation. She alleged that the negative response was used as a means to “discredit, intimidate, isolate and silence those raising unwelcome scientific questions.” Mostert also said that she had been willing to make edits to the study to address the journal’s concerns but that her revision was “ignored by the journal.” Her testimony framed the investigation as suppression of unwelcome findings, and it was reported widely by media outlets that had covered the study favorably. Scientific institutions, for their part, continued to review the paper on the basis of its methods and reasoning, and the eventual retraction shows that those reviews ultimately prevailed.
In its retraction notice, the BMJ stated that Mostert’s proposed edits would have been “insufficient.” That characterization suggests that the problems were not merely matters of wording or emphasis but went to the core of the paper’s scientific validity. The journal also said that Mostert was not available to cooperate with the investigation held by the Princess Máxima Center and that BMJ investigators initially could not contact her. When she later responded, the journal said, she told investigators that other researchers had done most of the work. The Princess Máxima Center’s report, which was completed as part of its own integrity investigation, “concluded … that the article pays disproportionate attention to the possibility that COVID-19 containment measures and vaccination might have caused excess mortality,” according to the BMJ’s retraction notice. “That excess mortality occurred, however, was known and not newsworthy,” the center wrote. “Despite the fact that the authors do not investigate the causes for excess mortality, the introduction and discussion of the article are largely focused on how to explain the excess mortality.” The center’s report also alleged that the study’s authors cherry-picked data to support their arguments and ignored data that opposed them. These are serious findings. Cherry-picking data is a form of bias that can turn a legitimate but incomplete analysis into a misleading one, especially in a subject with as much public importance as vaccine safety. A retraction of this kind is one of the most serious actions a journal can take, and the language used in the notice makes clear that the editors considered the paper to be not just flawed but harmful to the scientific record.
The original study was notable not because it had discovered that excess mortality occurred, but because of the interpretation it imposed on those numbers. Many countries saw higher-than-expected deaths during the pandemic, and epidemiologists attributed those deaths to a combination of COVID infections, delayed care, hospital strain, and other indirect effects. Excess mortality cannot, on its own, separate deaths caused by the virus from deaths that occurred in people infected with it, nor can it distinguish between deaths prevented by vaccines and deaths that vaccines may have caused. The study’s authors acknowledged that their analysis was not designed to prove causation. Yet they wrote in a way that encouraged readers to suspect that vaccines and containment measures were responsible for a large share of the excess deaths. Because the paper appeared in a peer-reviewed journal, it carried an appearance of scientific authority, and that appearance made its claims more dangerous than an ordinary blog post or preprint. Prominent vaccine skeptics and some Republican lawmakers cited the paper as evidence that COVID vaccines had killed millions. Those citations often omitted the authors’ caveats and overstated what the study actually found. The paper became part of a political narrative about government overreach and medical harm, and it was repeated so often that many people came to believe it was established fact. The retraction is a formal rejection of that narrative, but it cannot erase the years of amplification that occurred before the scientific review was complete.
The retraction raises larger questions about how scientific corrections can catch up to a paper that has already moved into public discourse. Peer review is meant to screen out flawed submissions, but it is not perfect, and some problems are only visible after a paper is examined by a wider community of experts. In this case, the journal moved quickly to open an investigation, but the formal retraction took more than a year. During that interval, the paper was presented to a congressional subcommittee and spread far beyond the scientific literature. Retraction notices are one of the most serious actions a journal can take, but they receive far less attention than original studies, especially when those studies have become political symbols. For some readers, the retraction will be taken as confirmation that the study was too dangerous to allow and that its authors were silenced. For others, it will be seen as a long-overdue correction of a misleading paper. The BMJ and the Princess Máxima Center both maintained that their reviews were based on scientific standards, not politics. The center’s finding of cherry-picking and its statement that the paper paid disproportionate attention to containment and vaccine harms are particularly damning, because they indicate a lack of balance that is fundamental to credible medical research. A study that begins with a conclusion and then selects data to support it is not a study; it is advocacy. Retractions serve to protect the integrity of the literature, but they are also blunt instruments. They cannot restore the time lost, the trust broken, or the thousands of times the flawed conclusion was repeated.
Scientific American has reached out to two of the study’s co-authors, pediatric oncologists Minke Huibers and Gertjan Kaspers, for comment. It is not immediately clear whether they plan to respond or whether they agree with the journal’s decision. What can be said is that the retraction is a formal statement about the paper’s place in the scientific literature, not about all possible questions concerning pandemic policy or vaccine side effects. The excess mortality observed in Western countries between 2020 and 2022 was real and remains a subject of epidemiological study. But this paper did not provide a rigorous explanation for it, and its discussion of causes was described by the journal as imbalanced and misleading. The journal’s use of the word “misinformation” is especially significant, because it moves the criticism beyond a technical error and into the realm of public harm. For public health officials, the episode underscores the need for transparent methods, careful language, and a fast response when questionable research begins to circulate. For vaccine skeptics, the retraction removes a central piece of evidence that had been used to argue that millions of people likely died as a result of COVID vaccines. Whether those who relied on the study will accept that removal is uncertain. What is certain is that the paper’s formal status has changed: it has been retracted, and it can no longer be cited as a valid source of evidence in scientific or policy debates.