Beware of causal fallacies in the hunt for COVID-19's origin

Kent Kroeger
5 min readAug 2, 2022

By Kent R. Kroeger (August 2, 2022)

Wuhan Institute of Virology in Jiangxia District, Wuhan, Hubei province, China (Photo by Ureem2805; used under the CCA-Share Alike 4.0 International license.)

With the formal release of two studies offering strong evidence that the initial epicenter of large-scale COVID-19 transmission centered on the Huanan Seafood Market in Wuhan, China, many in the news media and scientific community declared the end of the lab-leak theory in explaining COVID-19’s origins.

Matthew Aliota, a researcher in the college of veterinary medicine at the University of Minnesota who did not work on either of the studies, told the Associated Press that this new research “kind of puts to rest, hopefully, the lab-leak hypothesis.”

I wrote about these two studies four months ago when their pre-print versions were released to the public, and, while citing some critics of those studies, I too found myself moving away from the lab-leak theory as the most probable cause of the COVID-19 pandemic and towards the belief that COVID-19 has a zoonotic source (i.e., animal-to-human transmission).

Despite this latest research pointing at the Huanan Seafood Market as the earliest focal point for the virus’ mass transmission between humans, there remains no ‘smoking gun’—that is, scientists have yet to find evidence of the original SARS-CoV-2 virus residing in an animal species prior to the outbreak within humans.

Without that crucial evidence, it remains possible (though not necessarily likely) that a virus created and/or housed within the Wuhan Institute of Virology (or some other Wuhan lab) was inadvertently leaked into the environment, leading to an infected human spreading the virus in the crowded, poorly-ventilated Huanan Seafood Market.

The Intercept’s Ryan Grim noted recently on The Hill’s Rising podcast that China’s version of the Centers for Disease Control and Prevention (CDC) has a virology lab a mere 500 yards from the Huanan Seafood Market (see Figure 1) — a lab which has, in the past, been cited for inadequate biological containment and control practices.

Figure 1: Map of Central Wuhan and location of the Huanan Seafood Market relative to known virology labs

Kent Kroeger

I am a survey and statistical consultant with over 30 -years experience measuring and analyzing public opinion (You can contact me at: