Updated at 9:35 a.m. ET
A team of 13 World Health Organization scientists have now arrived in Wuhan, China, where they will investigate the origins of the coronavirus that has caused a global pandemic. Nearly 2 million people have died due to COVID-19, with more than 92 million infections, according to Johns Hopkins University.
"The experts will begin their work immediately during the 2 weeks quarantine protocol for international travelers," the WHO said Thursday.
"China has repeatedly pushed back against consensus that the novel coronavirus first appeared in humans in Wuhan," NPR's Emily Feng reports from Beijing. "Officials have suggested without evidence that the virus began elsewhere, including the U.S., and was brought to China."
Members of the team began the process of traveling to China more than a week ago, after discussions between the WHO, China's government and other countries the scientists would travel through on their way to Wuhan. The WHO announced the trip had begun on Jan. 5. But that same day, the international health agency was told that Chinese officials had not given final permissions for the team to arrive and begin their work.
"I am very disappointed with this news given that two members had already begun their journeys and others were not able to travel at the last minute," WHO Director-General Tedros Adhanom Ghebreyesus said at the time.
The scientists spent time in limbo in Singapore, waiting for final approval to enter China and travel to Wuhan.
"All team members had multiple negative PCR and antibody tests for COVID-19 in their home countries prior to traveling," the WHO said. "They were tested again in Singapore and were all negative for PCR. But two members tested positive for IgM antibodies," the agency adds, saying that those two scientists will now be retested for antibodies.
Chinese authorities have sought to keep information about the virus under tight control, punishing people for publishing information through unofficial channels.
The most famous case involved the late Li Wenliang, the ophthalmologist who was reprimanded after issuing early warnings about the coronavirus. Officials later apologized for Li's treatment. But the government recently imposed a four-year prison sentence on Zhang Zhan, the lawyer-turned-citizen-journalist who had been giving her own updates on the pandemic's effects in China.
More than one year after the first alarms were raised in China about an unknown pathogen that was then identified as the SARS-CoV-2 virus, the country has reported fewer than 100,000 cases, according to data compiled by Johns Hopkins.
In the past week, Chinese authorities have issued stay-at-home orders and other restrictions on 11 million people in Hebei province, concerned by a recent uptick in new positive tests.