A WHO team arrived in Wuhan to begin investigating the origin of the novel coronavirus, more than a year after it began to spread

• A team of experts sent by the World Health Organization arrived in Wuhan, China Thursday to begin an investigation into the origins of COVID-19.
• The novel coronavirus was first detected in the Chinese city more than a year ago, and is believed to have been transmitted to humans after originating in bats.
• It was not immediately clear how many members made it to China, after at least two were denied entry.

A team of experts sent by the World Health Organization arrived in Wuhan, China, on Thursday to begin an investigation into the origins of COVID-19.

The novel coronavirus was first detected in the Chinese city more than a year ago, and has since spread to all corners of the globe, leaving more than 92 million people infected and more than 1.9 million dead, according to data compiled by John Hopkins University.

Most of the team managed to reach Wuhan, though months after they hoped to be given access. According to the Associated Press, 10 people arrived Thursday.

However, another report, from The New York Times, spoke of a larger team, 13 of whom made it to Wuhan, and two of whom were denied en route in Singapore.

Business Insider could not immediately reach the WHO to confirm the true number.

The mission was approved after months of negotiations between the United Nations and President Xi Jinping.

China was slow to grant permission for the researchers to enter the country, prompting a rare public complaint from the WHO last week, The Wall Street Journal reported.

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President Donald Trump has long blamed the pandemic on China, which has challenged the accusation and claimed the virus came into the country from abroad. Scientists do not support that theory, according to the AP.

There are lingering concerns over the investigation, including whether China will be forthcoming with information that could cast the government in a negative light, AP reported.

The first confirmed case of the virus was in Wuhan on December 31, but some evidence suggests the virus may have been circulating in China and European nations months before that.

On the origin of the virus, researchers are fairly certain that it came to humans after developing in an animal, most likely bats. Lab tests show the novel coronavirus shares 80% of its genome with SARS, another virus that came from bats and triggered an epidemic in the early 2000s, Insider previously reported.

It is unclear how the virus got from bats to humans. The first infections were initially thought to have occured at a wet market in Wuhan, though some research suggested the market may have just been an early hub for infections rather than a point of origin.

The team of researchers plan to visit the market to investigate those possibilities, the Journal reported.