Where did it come from? More than three years into the pandemic with untold millions of people dead, that question about the origin of Covid-19 remains widely disputed and fraught, with facts sparkling amid a tangle of analyses and hypotheticals like Christmas lights strung on a dark, thorny tree. One school of thought holds that the virus, known to science as SARS-CoV-2, spread to humans from a nonhuman animal, probably in the Huanan Seafood Wholesale Market, an emporium brimming with fish, meats and wildlife on sale as food in Wuhan, China.

Another school argues that the virus was laboratory-engineered as a bioweapon to infect humans and cause them harm, and was possibly devised in a “shadow project” sponsored by the People’s Liberation Army of China. A third school, more moderate than the second but also implicating laboratory work, suggests that the virus got into its first human victim by accident at the Wuhan Institute of Virology, a research complex on the eastern side of the city, maybe after undergoing well-meaning but reckless genetic manipulation that made it more dangerous to people.

If you feel confused by these possibilities, undecided, suspicious of overconfident assertions — or just tired of the whole subject of the pandemic and whatever little bug has caused it — be assured that you aren’t the only one.

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The Sunday Read: ‘The Ongoing Mystery of Covid’s Origin’

The Daily

00:00The Origins of the Covid Virus

The Origins of the Covid Virus

03:32The Controversy of Covid's Origin

The Controversy of Covid's Origin

06:01The Origin Mystery of SARS-CoV-2

The Origin Mystery of SARS-CoV-2

10:48Multiple Perspectives on the Origin

Multiple Perspectives on the Origin

12:04Examining the Origins of Viral Outbreaks

Examining the Origins of Viral Outbreaks

16:45Exploring the Wuhan Lab and Wildlife Trade

Exploring the Wuhan Lab and Wildlife Trade

18:06The Origins of SARS-CoV-2

The Origins of SARS-CoV-2

23:15Debunking Conspiracy Theories

Debunking Conspiracy Theories

24:08The Origin of SARS-CoV-2 and Natural Virus Theories

The Origin of SARS-CoV-2 and Natural Virus Theories

25:19The RATG13 Genome Sequence and Lab Leak Speculations

The RATG13 Genome Sequence and Lab Leak Speculations

30:10The Emergence of the Lab Leak Theory

The Emergence of the Lab Leak Theory

35:09Shifting Public Opinion on the Lab Leak Theory

Shifting Public Opinion on the Lab Leak Theory

36:14Investigating the Origins of HIV-1M

Investigating the Origins of HIV-1M

39:30Controversies Surrounding the Origin Investigation

Controversies Surrounding the Origin Investigation

42:16The Origins of the Virus: A Closer Look

The Origins of the Virus: A Closer Look

47:21Shift in Perspective: Lab Leak Theory Gains Attention

Shift in Perspective: Lab Leak Theory Gains Attention

48:20The Origin of the Virus and the Huanan Market Connection

The Origin of the Virus and the Huanan Market Connection

51:51Public Opinion and Lab Leak Hypothesis

Public Opinion and Lab Leak Hypothesis

54:23Exploring the Origins of the Virus

Exploring the Origins of the Virus

57:54Understanding the Adaptability and Natural Host of the Virus

Understanding the Adaptability and Natural Host of the Virus