The year before the outbreak, the Wuhan institute, working with U.S. partners, had proposed creating viruses with SARS-CoV-2's defining feature. Much of this work was conducted in partnership with the EcoHealth Alliance, a U.S.-based scientific organization that, since 2002, has been awarded over $80 million in federal funding to research the risks of emerging infectious diseases. The laboratory pursued risky research that resulted in viruses becoming more infectious: Coronaviruses were grown from samples from infected animals and genetically reconstructed and recombined to create new viruses unknown in nature. In 2021, The Intercept published a leaked 2018 grant proposal for a research project named Defuse, which had been written as a collaboration between EcoHealth, the Wuhan institute and Ralph Baric at the University of North Carolina. The Defuse project proposed to search for and create SARS-like viruses carrying spikes with a unique feature: a furin cleavage site the same feature that enhances infectiousness in humans, making it capable of causing a pandemic. As the pandemic raged, their American collaborators failed to publicly reveal the existence of the Defuse proposal. One alarming detail " leaked to The Wall Street Journal and confirmed by current and former U.S. government officials " is that scientists ... fell ill with Covid-like symptoms in the fall of 2019. One of the scientists had been named in the Defuse proposal as the person in charge of virus discovery work. [This] would be the most costly accident in the history of science. U.S. federal funding helped to build an unprecedented collection of SARS-like viruses at the Wuhan institute, as well as contributing to research that enhanced them.