On March 11, 2020, the World Health Organization declared Covid-19 a pandemic, as the mysterious virus forced borders and businesses to shut down, crippled economies, ensured never previously seen lockdowns and claimed millions of lives. Yet, three years later, a central question at the heart of the world’s biggest public health crisis in a century remains unanswered: how did the virus first spread? That is not because of a failure of science but because competing geopolitical interests have turned what should have been a moment of global unity into a diplomatic war between China and the West that has pushed public health to the background. The result: a missed opportunity to prepare for the inevitable, next pandemic, whenever it comes. The latest escalation in the debate over Covid-19’s origins has come in recent weeks, with the department of energy of the United States of America claiming that the virus most likely emerged from a lab in Wuhan, China. But the agency also said that its assessment was based on “low confidence” intelligence, which raises questions about why it was shared with members of the US Congress in the first place. Subsequently, the Federal Bureau of Investigation’s chief said that his agency, too, has believed for some time that a lab leak was the most likely origin story for the virus.

Given the heightened tensions between China and the US, Beijing has predictably dismissed these suggestions. Indeed, multiple US intelligence agencies themselves had previously said they believed that the virus likely emerged from Wuhan’s wet market and spread to humans naturally. It is unclear what new evidence has made some US agencies conclude differently. Within the scientific community, research overwhelmingly — though not conclusively — points to natural transmission, and the evidence leans against the lab-leak theory. In fact, senior American scientists whose research has pointed to the wet market as the likely source of the virus have publicly questioned the department of energy’s latest assessment. But if the origin story of the pandemic remains a whodunit, China is at least as much to blame as its global rivals.

From hiding the contagious nature of the virus for weeks before sharing that information with the world, to repeated obfuscation of data, to its stonewalling of WHO’s investigations, China has been opaque since the beginning of the crisis. In recent weeks, it has started sharing more genomic sequences of Covid-19 strains with the international community of scientists than earlier. But unless it allows a full and transparent accounting of the early days of Covid-19, the world will never confidently know just what happened. Ironically, that hurts China the most and allows conspiracy theories to flourish. But worst of all, the uncertainty over the origins of the virus leaves countries around the world ill-prepared to prevent or stall the next public health crisis. At a time when science should have triumphed, politics has. The world has lost.