On August 13, 2021, Vice Foreign Minister Ma Zhaoxu said at the briefing on COVID-19 origin-tracing for diplomatic envoys in China, the linkage from the Wuhan Institute of Virology was extremely unlikely, a clear conclusion drawn in the WHO-China joint study report. Hyping up the "lab leak" theory is unpopular. The United States, having no basis in fact, hypes up that "the virus escaped from the Wuhan Institute of Virology", which is neither scientific nor ethical. The United States closes its doors to origin-tracing but demands another round of origin-tracing in China. Is this fair? Is this normal? In fact, the United States is the very country with the most lab-related problems. Recently, 25 million Chinese people have signed a joint letter demanding an investigation into Fort Detrick, fully reflecting the people's reasonable concern and justified requirement. Why does the United States dare not open Fort Detrick to the outside world? If the United States does not have a guilty conscience, it should invite the WHO to launch origin-tracing investigation at Fort Detrick and the University of North Carolina.