preventing more than 4,000 deaths in a single year
As the acute emergency of the pandemic gave way to routine management in late 2023, the question facing public health systems was no longer whether to vaccinate, but how wisely. A modeling study published on medRxiv in October examined Germany's choice between two updated COVID-19 boosters, placing the decision within the broader human calculus of lives preserved and resources spent. According to the simulation, Moderna's mRNA-1273.815 vaccine would prevent more than 4,000 deaths and 85,000 hospitalizations annually while costing less overall than its Pfizer counterpart — a finding that, though preliminary, offers a framework for navigating the quieter, more deliberate phase of pandemic stewardship.
- Germany faces a practical crossroads: with two XBB.1.5-targeted vaccines authorized, policymakers must determine which delivers the greater return on public health investment.
- Without any updated booster, the model projects nearly 11,000 deaths and over 300,000 hospitalizations in Germany within a single year — a burden that vaccination could substantially reduce.
- Moderna's vaccine outperforms Pfizer's not only clinically — preventing 157 additional deaths and over 90,000 more symptomatic cases — but also economically, qualifying as 'dominant' in health-economic terms.
- The study's credibility is constrained by its preprint status and its reliance on assumed uptake rates, borrowed effectiveness data, and a static view of variant evolution.
- Real-world impact hinges on whether people actually show up for boosters — and whether the vaccines perform in clinics as well as they do in mathematical models.
By early autumn 2023, the pandemic's emergency phase had passed. The WHO had declared the global health crisis over in May, and Germany had shifted to a quieter strategy: annual boosters for older adults and high-risk groups. Two new vaccines targeting the XBB.1.5 variant had emerged — one from Moderna, one from Pfizer. A modeling study posted to medRxiv in October asked which would do more good, and at what cost.
Researchers from Moderna built a mathematical simulation of Germany's disease burden between September 2023 and August 2024 under three scenarios: Moderna's mRNA-1273.815 vaccine, Pfizer's XBB.1.5 formulation, or no updated booster at all. The model covered high-risk adults aged 30 to 59 and everyone 60 and older, tracking infections, hospitalizations, deaths, medical costs, and lost productivity.
Without vaccination, the model projected 12.9 million symptomatic cases, over 305,000 hospitalizations, and more than 11,000 deaths. Moderna's vaccine would reduce that toll by preventing 1.6 million symptomatic infections, 85,000 hospitalizations, and over 4,000 deaths. Against Pfizer's alternative, Moderna's formulation prevented an additional 90,000 cases, 3,471 hospitalizations, and 157 deaths — and did so at lower total cost, earning the health-economic designation of 'dominant.'
The study's conclusions rest on assumptions: equal variant-matching between vaccines, effectiveness estimates borrowed from earlier trials, and uptake rates modeled on Germany's 2021–22 flu season. Crucially, the work has not yet been peer-reviewed, and the authors cautioned against treating it as clinical guidance. What it offers instead is a structured way of thinking about trade-offs in a post-emergency world — one where the question is no longer whether to vaccinate, but which vaccine earns its place in a more measured, resource-conscious public health strategy.
By early autumn 2023, the acute phase of the pandemic had passed. The World Health Organization had declared the global health emergency over in May, and across Europe, COVID-19 had shifted from crisis to routine. Germany, like other nations, had moved to a new vaccination strategy: annual boosters for older adults and high-risk groups, rather than the constant campaigns of the previous years. Into this quieter landscape came two new vaccines, both designed to target the XBB.1.5 variant that had begun circulating. Moderna and Pfizer each had a candidate. A modeling study, posted to the preprint server medRxiv in October 2023, attempted to answer a practical question: which one would do more good, and at what cost?
The researchers, working from Moderna, built a mathematical simulation of what would happen in Germany between September 2023 and August 2024 if people received either Moderna's mRNA-1273.815 vaccine, Pfizer's XBB.1.5 BNT162b2 vaccine, or no updated booster at all. They modeled two populations: adults aged 30 to 59 in high-risk categories, and everyone 60 and older. The simulation tracked symptomatic infections, hospitalizations, deaths, medical costs, and lost productivity. It assumed that uptake of the new vaccines would match the influenza vaccination rate from the 2021-22 season in Germany—a reasonable but not certain assumption.
Without any new vaccination, the model predicted a substantial disease burden over that twelve-month period: 12.9 million symptomatic cases, 305,711 hospitalizations, and 11,125 deaths. Moderna's vaccine, the model suggested, would reduce that toll significantly. Symptomatic cases would drop by 13.1 percent. Hospitalizations would fall by 27.9 percent. Deaths would decline by 36.8 percent. In absolute terms, that meant preventing more than 1.6 million symptomatic infections, more than 85,000 hospital admissions, and more than 4,000 deaths across Germany in a single year.
But the study's more pointed finding was the comparison between the two vaccines. Moderna's formulation came out ahead on both clinical and economic grounds. Compared to Pfizer's XBB.1.5 vaccine, Moderna's version would prevent an additional 90,000 symptomatic cases, 3,471 hospitalizations, and 157 deaths. The cost analysis, conducted from both a healthcare payer's perspective and a broader societal one that included lost wages and productivity, found Moderna's program to be what health economists call "dominant"—meaning it delivered better health outcomes at lower total cost. There were fewer quality-adjusted life-years lost, and the direct medical expenses were smaller.
The findings rest on several assumptions baked into the model. The researchers assumed both vaccines were equally well-matched to the circulating variant. They borrowed effectiveness estimates from earlier trials and from comparative studies of Moderna and Pfizer's bivalent boosters. They assumed vaccination coverage would follow the pattern of flu shots in Germany two years prior. These are reasonable working assumptions for a modeling exercise, but they are assumptions nonetheless. The study was posted to medRxiv, a preprint server where researchers share findings before peer review. That designation matters: the work has not yet been vetted by independent experts, and the authors themselves noted that preprint findings should not be treated as conclusive or used to guide clinical decisions.
What the study does offer is a framework for thinking about the trade-offs between two similar products in a post-emergency phase of the pandemic. Germany had already authorized both vaccines for people 12 and older. The question was not whether to vaccinate, but which vaccine would yield the better return on public health investment. According to this modeling, Moderna's formulation would deliver more protection per euro spent. Whether that advantage would hold up in real-world conditions—in actual vaccination clinics, with real people making real choices about whether to get boosted—remains an open question. Uptake rates, variant evolution, and the actual performance of the vaccines in the field could all shift the calculus. But for policymakers weighing options in the autumn of 2023, the study suggested a clear preference.
Citações Notáveis
The mRNA-1273.815 vaccination program was dominant from a healthcare payer and societal perspective and estimated to have lower total direct medical and indirect costs, with fewer quality-adjusted life-years lost, than the XBB.1.5 BNT162b2 vaccination.— Study findings
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Why does it matter which vaccine Germany chose, if both were already authorized and available?
Because resources are finite and decisions compound. If one vaccine prevents more deaths at lower cost, that's a meaningful difference at scale. Over a year, we're talking about thousands of lives and millions in savings that could go elsewhere in the health system.
But this is a model, not real data. How confident should we be in these numbers?
Cautiously. The researchers used reasonable assumptions—they borrowed effectiveness data from trials, matched uptake to historical flu vaccination patterns. But models are only as good as their inputs. The real world is messier. People might not get vaccinated at the rates assumed. The virus might evolve differently. That's why it's a preprint, not yet peer-reviewed.
What's the practical difference between the two vaccines, from a patient's perspective?
Probably very little. Both target the same variant. Both are mRNA vaccines with similar side effect profiles. The difference the study found is in the degree of protection—Moderna's appears slightly more effective against this particular variant. But for an individual deciding whether to get boosted, either vaccine is far better than nothing.
The study was done by Moderna. Doesn't that create a conflict of interest?
It does raise a flag. Moderna funded the research and conducted it. That doesn't mean the findings are wrong, but it does mean independent verification matters. Peer review will help. Real-world data comparing the two vaccines in practice will matter more than any model.
What happens next? Does Germany use this to make a policy decision?
Possibly. Health authorities will look at this alongside other evidence—other studies, real-world effectiveness data as it emerges, input from advisors. A single preprint, even a well-designed one, doesn't drive policy alone. But it's part of the conversation.