The international community, including China, has every reason to raise questions about Fort Detrick and call on the World Health Organization (WHO) to thoroughly investigate it for the safety of people in all countries, Foreign Ministry spokesperson Zhao Lijian said on July 22.

On the issue of COVID-19 origin-tracing, some people in the United States may indeed have a guilty conscience, Zhao said, adding that the U.S. side has remained silent on the serious concerns raised by the international community about Fort Detrick and the more than 200 biological laboratories overseas.

"The U.S. side must understand that the international community, including China, has every reason to raise questions about Fort Detrick, which has a poor track record and is notorious for breaches in lab and contaminant leak, and demand clarification and explanation from the U.S. side and call on the WHO to conduct a thorough investigation into it," Zhao said at a daily press briefing.

This requirement is not only for tracing the source of COVID-19, but also for the safety of people in all countries, he said. "The questioning will not end until the U.S. side gives a reasonable explanation."

At the briefing, Zhao made comments on a media report that scientists from two labs in Italy, including Milan's Istituto Nazionale Tumori, a cancer research centre, wrote in a new paper published on July 19, that retesting of a small number of pre-pandemic blood samples had indicated the presence of antibodies normally observed after coronavirus infections.

Zhao said for some time, more and more reports have pointed to separate outbreaks in multiple places in the world in the latter half of the year 2019, and at least five states in the United States alone had earlier COVID-19 infections before the first officially reported confirmed case.

This again shows that origin-tracing of COVID-19 is a complex scientific matter, which calls for a global collaboration of scientists with a global perspective, he said.

However, some people in the United States still ignore science and facts. Obsessed with political manipulation, they are hyping up the so-called "lab leakage theory," advocating intelligence-led origins study, suppressing and threatening experts and scholars who are making an objective and rational voice, in an attempt to shift responsibility for their botched epidemic response by discrediting other countries, Zhao said.

"Some individuals in the US put politics above science and selfish political gain above people's lives and health, which in large part accounts for the poor epidemic response," he said.