Keep lab theory on table

The scientific community has been divided over what to make of the virus’s origin clues till now. In early May, science writer Nicholas Wade cited existing research to support the need to keep the lab leak theory on the table.

Wade included several arguments: One, if the virus was naturally found in the famous horseshoe bats of Yunnan, how, or whether at all, did it travel to Wuhan, at least 1,500km away; two, how the Sars-CoV-2 virus appeared to have come fully evolved to optimally target humans, unlike the Sars-CoV virus, responsible for South Asia Respiratory Syndrome, that evolved over time; and three – a unique protein folding known as the furin cleavage site in this virus, which has not been found in other betacoronaviruses.

Some scientists have disputed the biological inferences being drawn, particularly in the context of the furin cleavage site. “FCSs (furin cleavage sites) are abundant, including being highly prevalent in coronaviruses. While SARS-CoV-2 is the first example of a SARS virus with an FCS, other betacoronaviruses (the genus for SARSCoV-2) have FCSs, including MERS and HKU1,” wrote immunologist and infectious disease genomics specialist at Scripps Research Institute, Kristian G Andersen, in a tweet on May 10.

The questions about what clues China may hold are further strengthened by the lack of a resurgence in cases in the country. A country with the world’s highest population, China has recorded no new wave of infections since when the outbreak began.

It recorded 7,280 new cases at its peak, on February 14, 2020, and the only time infections rose again in any significant manner was in mid January, 2021, when the 7-day average of new cases was a little under 2,000 for a few days.