COVID-19 emerged in China around October 2019, not December: Study
Ever since the COVID-19 pandemic broke out across the globe, scientists have been trying to find the origins of SARS-CoV-2—the novel coronavirus that causes the deadly disease—to understand when and where the spread actually began. While the first official case had been recorded in China in December 2019, a new study suggests that it could have emerged there way earlier than estimated. Here's more.
Using methods from conservation science, researchers from the United Kingdom's University of Kent estimate the spread of the novel coronavirus in China could've begun as early as October 2019—two months before Wuhan registered the first official case. "Results infer that SARS-CoV-2 emerged in China in early October to mid-November, and by January, had spread globally," said the study published in the PLOS Pathogens journal.
The new study puts the most likely date for the emergence of the virus in China based on its model as November 17, 2019, before it spread globally by January 2020. China's first known case was linked to Wuhan's Huanan seafood market, but the study suggests the virus was circulating even before reaching this market as some early cases showed no connection with Huanan.
To recall, a joint study by the World Health Organization (WHO) and Chinese researchers on the origin of COVID-19, published recently in March, also acknowledges that sporadic infections in human beings could have been caused much before the Wuhan outbreak. Based on molecular evidence, this study estimated the range of the origin of the virus could be between late-September and early-December, reported Forbes.
Interestingly, the latest study by UK researchers comes after a scientific paper revealed on Wednesday that sequencing data of cases from the early months of the pandemic in China was deleted from a shared international database used for tracking the virus's evolution. It was authored by Jesse Bloom—a virologist and an evolutionary biologist at Seattle's Fred Hutchinson Cancer Research Center—who recovered the deleted data.
In his report, Bloom stated early samples were a "gold mine for anyone seeking to understand the spread of the virus." "The fact that such an informative data set was deleted has implications beyond those gleaned directly from the recovered sequences. There is no plausible scientific reason for the deletion...It, therefore, seems likely the sequences were deleted to obscure their existence," he added.
Meanwhile, several critics said that China deleting the crucial data related to early COVID-19 cases is another attempt by the country to cover up the virus's origins. "Why would scientists ask international databases to delete key data that informs us about how COVID-19 began in Wuhan? That's the question you can answer for yourselves," tweeted Alina Chan, a researcher with Harvard's Broad Institute.