A new report contends that Covid-19 most likely leaked from a Chinese lab, with America partly responsible for funding high-risk research on infectious viruses at a facility with insufficient safety measures.

The analysis, conducted by a molecular biologist at Harvard and MIT, Alina Chan, was published as a guest essay in the New York Times on Sunday. The report came before Dr. Anthony Fauci was set to testify before a House panel regarding his support for research at the Wuhan Institute of Virology.

Ms. Chan, who has been an advocate for further investigation into the “lab leak theory,” said that partisan politics have hindered efforts to uncover the truth about the origins of the pandemic.

If the theory proves accurate, the global pandemic, which has claimed around 1 million lives in the US and at least 25 million worldwide, could be considered the most significant accident in the history of science, according to Ms. Chan, co-author of “Viral: The Search for the Origin of Covid-19.”

Her findings suggest that the virus originated in China, was intensified for maximum infectiousness with the assistance of the American government, and eventually escaped due to inadequate containment protocols.

Scientists at the Wuhan Institute of Virology, led by Dr. Shi Zhengli, spent more than 10 years researching SARS-like viruses to understand how they infect humans. Their research identified that SARS-CoV-2, the virus responsible for the pandemic, existed in bats located approximately 1,000 miles away from Wuhan.

Dr. Shi’s team made several trips to southwestern China and Laos to collect virus samples, which traveled through numerous populous cities on their way back to the Wuhan lab.

Despite the virus’s high contagion rate, no trace of infection was found along the 1,000-mile route, Ms. Chan reported. Her research also dismissed an early theory that the virus had spread globally via a seafood market at Wuhan, where exotic animals were sold for consumption.