Pedestrians walk past a COVID-19 testing site on Times Square in New York, the United States, May 17, 2022. (Xinhua/Wang Ying)

As almost all countries have re-embraced normal life one by one, COVID-19 is gradually fading off the world's most searched hashtags list, giving way to more crucial topics such as the Ukraine crisis and the enduring gun problem in the United States. However, the same old tune of "China lab leak theory" has lately once again struck up by U.S. officials for some reason.

In the past three years, such remarks made by some U.S. politicians were just like mosquitoes in warm damp air -- they kept buzzing around no matter how constantly slapped by facts and evidence. At the beginning of the outbreak, while China participated in science-based global origins-tracing of the virus, Washington, ignoring the spiraling number of domestic patients, clamored for an investigation in China.

In February 2021, after a four-week investigation as some U.S. officials had once pushed for with all efforts, experts of the WHO-China joint mission reported that "a laboratory origin of the pandemic was considered to be extremely unlikely." But clearly, this science-based authoritative conclusion is not as "desirable" as what the U.S. government wishes. Not very long after, U.S. President Joe Biden turned to the intelligence community for a COVID-19 virus origins story despite voices from around the world calling for "give to science what belongs to science." Unsurprisingly, U.S. intelligence agencies failed to satisfy the White House's tireless intention to incriminate China.

This photo taken on March 29, 2023 shows the White House in Washington, D.C., the United States. (Xinhua/Liu Jie)

This March, the U.S. Congress passed the COVID-19 Origin Act of 2023, which iterated that the pandemic may have originated in China. After the U.S. government's three-year-long "investigation," or fabrication to be precise, its Energy Department concluded with "low confidence" that "an accidental laboratory leak" in China "most likely" caused the pandemic, as unsure as three years ago.

Obviously, the United States is by no means unaware of the extremely low potentiality of the "China lab leak theory." It only expects to achieve political goals through hyping up this assumption out of nothing.

On the one hand, it blames China as if doing so could cover up its own problems in domestic governance such as ineffective pandemic control, high inflation, a wide gap between the rich and the poor, and racial conflicts, among others. On the other hand, by repeating the lie over and over again, the United States tries to influence and mislead international public opinion and achieve the Goebbels effect of turning lies into truth.

If, in any case, the virus was created by humans like some common routine in U.S. science fiction movies, there would be not much answer left about which countries are capable of doing so. In fact, more clues from the international science community are pointing to the U.S. origins of virus.

A man wearing a face mask is seen on a street in Washington, D.C., the United States, on Dec. 16, 2022. (Photo by Ting Shen/Xinhua)

Since the outbreak of the COVID-19 pandemic, the United States has neither invited the WHO experts team to conduct collaboration on origins-tracing, nor provided any early data about the outbreak, let alone taking seriously the concerns of the international community regarding the U.S. Fort Detrick Biological Laboratory, the University of North Carolina Biological Laboratory and U.S. military biological bases around the world.

Scientists have noted that the origins-tracing of any virus normally requires long-term research and extensive sample collection, which can take years or even decades. By rushing to conclude the origin of the virus, smearing China with unfounded excuses and covering up their own problems, U.S. politicians show neither responsibility to science nor respect for the tremendous efforts made by all mankind against the pandemic.

Now, the onus is on the United States to give the world a reasonable explanation.

The author is a commentator on international affairs, writing regularly for Global Times, China Daily etc.