Global · September 2020 — By the autumn of 2020, the scientific publishing landscape had undergone a transformation that would have been inconceivable just months earlier. The COVID-19 pandemic catalysed an unprecedented surge in the use of preprint servers—most notably bioRxiv and medRxiv—fundamentally altering how biomedical research is disseminated, debated, and translated into policy. What had been a niche practice, common in physics but controversial in the life sciences, became essential infrastructure for the global pandemic response.
The Scale of the Surge
In the first four months of the pandemic alone, thousands of COVID-19-related scientific articles were hosted on preprint servers. medRxiv, launched in June 2019 as a preprint server for health sciences, saw its submission rates multiply several-fold. bioRxiv, its older sibling for biological sciences established in 2013, experienced a similar influx. Together, the two platforms became the primary channels through which researchers shared findings on viral genomics, epidemiological models, clinical observations, vaccine candidates, and therapeutic trials.
The acceleration was driven by necessity. Traditional peer review, while essential for quality assurance, typically takes months from submission to publication—a timeline incompatible with a rapidly evolving pandemic. Preprint servers allowed researchers to share data within days of completing analysis, enabling the global scientific community to build on each other's work in real time.
A Cultural Shift in Biomedicine
Preprints have a long history in physics and mathematics, where the arXiv repository has been the dominant mode of communication since the early 1990s. In the biomedical sciences, however, preprints were met with greater resistance. Concerns about unreviewed findings influencing clinical practice, the potential for media misinterpretation, and the fear that journals would refuse to publish work already available as a preprint all contributed to slow adoption.
The pandemic shattered these barriers. When Chinese researchers posted the SARS-CoV-2 genome sequence on a preprint server in January 2020, it enabled vaccine developers worldwide to begin designing candidates within hours—a timeline that would have been impossible if they had waited for formal journal publication. This single event demonstrated the practical value of preprints in a public health emergency and set the tone for the year that followed.
Researchers who had never posted a preprint before 2020 became regular users. Institutions that had no formal preprint policies adopted them. Funders, including the Wellcome Trust and the National Institutes of Health, issued statements encouraging grantees to share COVID-19 findings as preprints. The cultural shift was rapid and, in many cases, irreversible.
Preprints in the Public Eye
For the first time, preprints moved beyond purely academic circles to receive significant attention from mainstream media, policymakers, and the general public. Journalists covering the pandemic routinely cited preprints in news articles, sometimes without clearly distinguishing them from peer-reviewed publications. Government advisory bodies referenced preprint data in their recommendations. The general public, hungry for information about the unfolding crisis, encountered preprints through social media and news coverage.
This unprecedented visibility sharpened both the benefits and the risks of preprint dissemination. On one hand, rapid sharing enabled faster scientific progress: when a preprint described a promising vaccine candidate or a concerning viral mutation, researchers worldwide could immediately incorporate those findings into their own work. On the other hand, preliminary findings that were later revised or retracted could generate public confusion or policy missteps.
Quality, Reproducibility, and the Risks of Speed
The rapid influx of COVID-19 preprints raised legitimate concerns about scientific quality and reproducibility. Studies analysing COVID-19 preprints found that many lacked clear markers for open data or open code, posing challenges for other researchers attempting to verify or build on the findings. The absence of peer review meant that methodological flaws, statistical errors, and overstated conclusions could propagate before being identified.
Several high-profile preprints were later found to have significant methodological problems. A widely reported preprint suggesting that COVID-19 mortality rates were far lower than initially estimated was withdrawn after statisticians identified fundamental errors in the sampling methodology. Another preprint promoting a controversial drug treatment gained widespread media attention before being debunked by subsequent peer-reviewed studies.
However, proponents of preprints argued that the open, rapid-feedback model of preprint servers actually facilitated faster correction of errors than the traditional journal system. When a preprint contained errors, the scientific community could identify and discuss them publicly within days, whereas errors in published journal articles might go uncorrected for months or years.
Citation Challenges
Research into COVID-19 preprint citation practices revealed additional complications. Some articles cited preprints that had already been published in peer-reviewed journals—often with substantially revised content—without acknowledging the final version. This created a form of scholarly record fragmentation, where different sources cited different versions of the same work, potentially with conflicting conclusions.
The problem was exacerbated by the sheer volume of COVID-19 literature. By mid-2020, the rate of publication on COVID-19 exceeded the capacity of any individual researcher to keep up, leading to selective reading and citation practices that sometimes prioritised speed over accuracy.
The Balance Between Speed and Rigour
The pandemic-era reliance on preprints sparked an ongoing debate about the balance between the moral imperative to share findings quickly during a public health emergency and the need to mitigate the risks of unverified, preliminary information. There was broad consensus that rapid sharing was necessary; there was less agreement on how to ensure that preprints were clearly labelled, responsibly reported by media, and appropriately weighted in policy decisions.
Several initiatives emerged to address these tensions. The COVID-19 Preprint Server, a dedicated channel on both bioRxiv and medRxiv, implemented rapid screening processes to flag obviously flawed submissions. Organisations like ASAPBIO (Accelerating Science and Publication in Biology) developed guidance for researchers, journalists, and policymakers on how to interpret and communicate preprint findings responsibly.
Long-Term Implications for Scientific Publishing
The experience of 2020 positioned preprint servers as permanent, long-term infrastructure for the scientific publishing ecosystem. Many journals that had previously refused to consider manuscripts already available as preprints reversed their policies. The NIH, in its 2020 policy updates, explicitly encouraged preprint posting for COVID-19 research and signalled a broader openness to preprints across all funded research.
The pandemic also accelerated experiments with alternative publishing models, including transparent peer review (where reviewer comments are published alongside the article), registered reports (where peer review occurs before data collection), and overlay journals (that formally peer review and publish articles already available as preprints). These models, long advocated by open science proponents, gained new urgency and institutional support.
Sources
- Fraser, N. et al., "The COVID-19 preprint landscape," bioRxiv, 2020
- NIH PMC, analysis of preprint usage during COVID-19 (PMC8046348, PMC9252536, PMC12892954)
- ASAPBIO, "Preprints and COVID-19," asapbio.org/preprints-and-covid-19
- bioRxiv and medRxiv, COVID-19 dedicated channels and submission statistics
- Fraser et al., "Preprinting a pandemic in the age of social media," 2021
- American Society for Microbiology, analysis of preprint citation practices, mBio, 2025
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Institutional Research Desk · Foresight Institute of Research and Translation
The collective editorial and research translation board of FIRAT, synthesising peer-reviewed evidence, policy briefs, and division milestones across our seven foundational research pillars.
