It’s understandable that the origin of COVID-19 has been the subject of major public intrigue. It’s unsurprising that it’s an issue that’s also been heavily politicised. 

Trump administration officials pushed the theory that the virus leaked from a Chinese lab – the Wuhan Institute of Virology, which specialises in the study of bat pathogens. Despite a lack of conclusive evidence, Secretary of State Mike Pompeo stated that there was “enormous evidence” that the virus was lab-born. Joe Biden has since called for a rapid intelligence report into COVID’s origins. 

There’s a lot of media noise echoing around this issue; what hard facts do we actually have? 

The wet food market 

A number of the earliest COVID-19 cases in Wuhan occurred in people who all had links with the Huanan Seafood Wholesale Market. 

Wet markets are typically open-air stalls that sell fresh meat, fish and produce; some sell wild animals and their meat. The Huanan market, for example, sold live and slaughtered animals including snakes, baby crocodiles and porcupines. This trade of wild animals for food can lead to an animal-borne disease infecting humans. Animals housed in cramped, dirty conditions can cause viruses to spread more easily, with pathogens intermingling and swapping parts of their genetic code. These conditions can also enable viruses to mutate and become transferrable between species. 

Research has been conducted into the Huanan market as the potential source of COVID-19. For example, it’s been found that in the two years prior to the pandemic, markets in Wuhan sold almost 30 animal species that are known to harbour pathogens that can be transferred to humans. However, no findings have been conclusive. The WHO experts who examined evidence from the Wuhan market reached no decisive conclusion about the market’s potential role in the pandemic, or even the animal through which the virus may have been passed on to a human.

Lab leak 

The so-called lab leak theory has stemmed from the information that three researchers at the Wuhan Institute of Virology were ill in November 2019 with COVID-like symptoms, with the three individuals requiring hospital treatment. As mentioned, this is a theory that was promoted by members of the Trump administration. 

The lab-leak hypothesis appeared to have been granted a degree of credibility by Nobel laureate David Baltimore’s comments on COVID-19’s novel furin cleavage site, a feature of COVID’s genome that is partly responsible for the virus’ high infectiousness. The scientific debate on the furin cleavage site has focused on whether the site is so unusual that it occurred through human tampering rather than natural evolution. Baltimore was quoted observing that the site was a “smoking gun” for the theory that the virus was lab-born. However, he has since said he overstated the case, clarifying that “he wouldn’t rule out either origin”, being lab-born or occurring naturally. In support of the furin cleavage site as a naturally occurring feature of COVID-19, other scientists have observed that the site also features in other common coronaviruses, such as those that cause a common cold. 

Much as with the wet food market, these findings do not serve as conclusive evidence for the lab-leak theory.

Natural evolution 

A group of scientists from a US non-profit medical research organisation looked into COVID-19’s genetic sequence and determined that the virus evolved in animals, highlighting potential sources as bats or pangolins. Another set of scientists published a joint statement supporting the virus’ natural origin in The Lancet. There are multiple independently published studies determining that the COVID-19 virus is the product of natural evolution from animals.


So, looking at the hard facts available, where did COVID-19 come from? It makes for a drab headline: ‘we don’t know’. 

Scientific research appears conclusive on the virus as naturally evolving. However, a clear geographic origin of the virus cannot definitively be pinned down. There’s still so much we don’t know about this virus and its origins, and perhaps won’t know for years. Ebola, for example, was identified in 1976 and to date scientists do not know which animal transmitted it into the human population. HIV’s origins are believed to be in chimpanzees in southeastern Cameroon, infecting the human population in the 1920s when the disease reached Kinshasa, a city hundreds of miles away. This discovery was only made in 2014, decades after the AIDS epidemic. 

The various findings about COVID-19’s origins – ranging from the likely to the inconclusive to the improbable – have not stopped media and politicians’ hypothesising and accusation that has stirred the proverbial global pot. Part of the problem is a reluctance on all sides to look at the facts and work hard to grapple with complex ideas and events, the other is a culture that demands immediate answers. ‘We don’t know’ simply won’t do.