Investigations into the origins of viruses are a complicated scientific issue, and often take years or even decades to complete.

Thus US President Joe Biden's intention was questioned when he gave his intelligence officers, rather than scientists or virologists, the task of determining where the COVID-19 virus had come from, and ordered them to report back in just 90 days.

The loaded way in which Biden has approached this serious scientific issue shows that he doesn't care much about the facts or the truth. He is more interested in giving some substance to the US narrative that blames China for the COVID-19 pandemic.

A two-page summary report of the investigation's "findings" was published in August, which China brushed aside as "not scientifically credible".

Clearly feeling that the intended message had not got across, the US Office of the Director of National Intelligence offered an updated intelligence briefing on Saturday, in which it asserted that a natural origin and a lab leak were both considered plausible hypotheses for the origin of the novel coronavirus, although it admitted the truth may never be known.

Since the US has been pushing the claim that the virus leaked from a virology laboratory in Wuhan, it was justifiable that China's Foreign Ministry should reject the "findings" announced by the US Office of the Director of National Intelligence, with spokesman Wang Wenbin saying that "a lie repeated a thousand times is still a lie".

Apart from the lab-leak theory, the intelligence report also accuses China of withholding major data and trying to hinder the global investigation into the origin of the virus.

Which is not true. China has always called for an objective, scientific, and responsible attitude in the tracing of the origins of COVID-19, and cooperated closely with the World Health Organization in this regard. A joint study by China and the WHO published early this year already concluded that it was "extremely unlikely" that the novel coronavirus had spread to humans through a laboratory leak. And scientists have not been able to identify any new evidence that might give any credit to the lab-leak hypothesis.

The US blame game against China will only become a joke for the world.

The WHO has launched a new task force, the Scientific Advisory Group on the Origins of Novel Pathogens, comprising 26 global experts, calling it "the last chance" to identify the origin of the virus. China has made it clear it will support and participate in this new endeavor.

Promoting the concept of a community of common health for mankind, China is playing its due part in the global fight against the pandemic.