Ever since the COVID-19 pandemic began, one question that has repeatedly cropped up is that of the origin of the virus itself.

While some believe that the virus came from bats in a Wuhan animal market, there are many who believe that the escape virus escaped from the Wuhan Institute of Virology.

According to the report of a scientist that was published on Thursday, 18 November, the first patient to be infected with COVID was a vendor in an animal market in Wuhan, reported The New York Times.

The study led by Dr Michael Worobey, head of ecology and evolutionary biology at the University of Arizona, emphasises on the discrepancies in the timeline of events which are available in the public domain, and criticises the early chronology which was made public by authorities.

The study particularly criticises World Health Organization's March report which, according gth Dr Worobey has faulty data, and may have been instrumental in fuelling the 'lab leak' theory.

Michael Worobey is an expert tracer of the evolution of viruses, at the University of Arizona.

The scientist says that the link between the vendor of the Huanan Seafood Wholesale market and the early hospitalised COVID-19 patients almost proves that the virus originated there, reported The New York Times.

Dr Worobey's findings don't necessarily settle the debate surround the origin of the pandemic, but it is a significant step towards it.

Dr Worbey's theory is backed by many experts and scientists around the globe.

However, there are also many who think that the evidence is insufficient. They hold that it is possible that the virus first infected another "patient zero", before the vendor which might have caused it to spread in the market, according to The New York Times.

Studies point to evidence suggesting that the first infection took place in November 2019.

The refuting scientists argue that this was weeks before the first COVID-19 case was detected in the vendor, and that Dr Worobey also did a study that suggested this.

Dr Jesse Bloom also said that the WHO report itself had errors, and this was not the first time such a thing has happened.

In the end of December 2019, doctors in Wuhan Hospital noticed a surge in pneumonia cases. Most of the patients happened to be workers at the Huanan Seafood Wholesale Market.

On 30 December, new pneumonia cases from the market were recorded, as per the public health officials.

The Huanan market was closed on 1 January 2020 as the Chinese officials feared a comeback of SARS, which had broken out in the Chinese animal markets in 2002.

But in spite of the markets being shut down, the cases only multiplied.

The WHO report, identified a 41-year-old accountant, who had reportedly started experiencing symptoms on 8 December, as being the first case, or 'patient zero'.

This was one of the reasons, the 'lab leak' theory gained steam.

This, in spite of the WHO repeatedly maintaining that the lab leak was 'unlikely'.

In the month of May, Dr Worobey and eighteen other scientists said, in a letter, that the WHO team didn't follow up the lab leak theory sufficiently enough to rule it out like they did.

According to Dr Worobey's report, the first COVID-19 patient is not Mr Chen, rather, a seafood vendor named Wei Guixian who developed symptoms around 11 December.

Dr Worobey also discovered that the hospitals had more cases of COVID-19 before 30 December than were reported.

Although more research is required to completely solidify Dr Worobey's theory, at the very least, it throws light on the discrepancies in the information that have been made public so far.

“The main issue this points out is that there’s a lack of access to data, and there are errors in the WHO-China report,” Alina Chan, a postdoctoral fellow at the Broad Institute in Cambridge, was quoted as saying by the New York Times.

(Written with inputs from The New York Times and Reuters.)