There are several ongoing efforts by scientists, governments, international organisations, and others to determine the<unk>  of SARS-CoV-2, the virus responsible for the<unk> -19 pandemic. Most scientists say that as with other pandemics in human history, the virus is likely of zoonotic<unk>  in a natural setting, and ultimately<unk> ated from a bat-borne virus. Several other explanations, including many conspiracy theories, have been proposed about the<unk> s of the virus. SARS-CoV-2 has close genetic similarity to multiple previously identified bat coronaviruses, suggesting it crossed over into humans from bats. Research is ongoing as to whether SARS-CoV-2 came directly from bats or indirectly through any intermediate hosts. Initial genome sequences of the virus showed little genetic diversity, although subsequently a number of stable variants emerged (some spreading more vigorously), indicating that the spillover event introducing SARS-CoV-2 to humans is likely to have occurred in late 2019. Health authorities and scientists internationally state that as with the 2002–2004 outbreak of SARS-1, efforts to trace the specific geographic and taxonomic<unk> s of SARS-CoV-2 could take years, and the results could be inconclusive. In January 2021, the World Health Assembly (decision-making body of the World Health Organization, WHO) commissioned a study on the<unk> s of the virus, to be conducted jointly between WHO experts and Chinese scientists. In March 2021, the findings of this study were published online in a report to the WHO Commissioner-General. Echoing the assessment of most virologists, the report determined that the virus most likely had a zoonotic<unk>  in bats, possibly transmitted through an intermediate host. It also stated that a laboratory<unk>  for the virus was "extremely unlikely." Scientists found the conclusions of the WHO report to be helpful but noted that more work was needed. In the United States, the European Union, and other countries, some criticised the lack of transparency and data access in the report's formulation. The WHO issued its 30 March report alongside a statement of the WHO director-general Tedros Adhanom Ghebreyesus saying that the matter "requires further<unk> . The U.S. government and 13 other countries and the EU issued statements on the same day, echoing Tedros's critique of the report for lacking transparency and data access in its formulation. In a later press conference, the WHO director-general said it was "premature" for the WHO's report to rule out a potential link between a laboratory leak and called on China to provide 'raw data' and lab audits in a second phase of<unk> . On 12 October 2021, WHO announced a new team to study the<unk> s of the<unk> -19 pandemic. Earlier, on 22 July 2021, the Chinese government had held a press conference in which Zeng Yixin, Vice Health Minister of the National Health Commission (NHC), said that China would not participate in a second phase of the WHO's<unk>  denouncing it as "shocking" and "arrogant".
Investigations into the origin of COVID-19
Treatment and management of COVID-19
Discovery of disease-causing pathogens
Chinese government response to COVID-19
Vaccine storage
Coordinated diagnostics
Wastebasket diagnosis
Connecting Organizations for Regional Disease Surveillance