Reading list: COVID-19 lab leak hypothesis

I’ve assembled a reading list below of articles discussing the possibility that a lab accident at the Wuhan Institute of Virology was the source of COVID-19. This topic has been political from the start, with the Chinese government censoring scientists and running a disinformation campaign, and the Trump administration accusing China of engineering the virus as a weapon. Now that Trump is no longer president, the lab leak hypothesis has been gaining momentum as journalists and scientists feel like they can speak up without being tied to conspiracy theories.

There is a case to be made, based on circumstantial evidence, that the whole pandemic could have begun as a lab accident. It certainly seems suspicious that the outbreak began in a city with no bat caves and down the street from the Wuhan Institute of Virology, the lab with the world’s largest collection of bat coronaviruses, which had known safety issues and was researching how bat viruses could jump to humans. It’s not far-fetched to think that they were successful in their research but lax with safety protocols, and the pandemic began when lab employees accidentally infected themselves.

The lab accident hypothesis could be disproven either by locating the genetic ancestor of the virus in an animal population somewhere, or through a forensic investigation of the lab to show that none of the viruses ever in their possession were the ancestor of COVID-19. However, a year has passed with no plausible natural source having been found, and the lab has not been investigated even though it would seem to be in China’s interest to allow it if they knew for certain the lab were not the source. If the COVID-19 pandemic really was the result of a lab accident, it may be that we will simply never have a conclusive answer to the origin question.

Here’s the list of articles, which I will continue to update:

Vibration reduction on DSLR camera lenses

Here is an answer to a photography question I had for a while: If vibration reduction (VR) on DSLR lenses results in sharper images a low shutter speeds, why would you ever want to turn it off? I remember once checking the Nikon manual, which recommended turning off VR when using a tripod, but did not offer much explanation. Last week while on a ski trip to Lake Tahoe I experienced the importance of this recommendation. While exploring Donner Pass on an off day, I tried taking this picture of me and my dad. I used the timer and rested the camera on a post for the shot. Here’s the final result:

View of Donner Lake from the top of Donner Pass. Truckee, CA.

It was a bright day, so I used a small aperture and fast shutter speed. After attempting the shot I noticed that our faces were slightly blurry. Thinking I had somehow missed focus, I tried again with similar results. Then I tried manual focus, same result. Finally I noticed that the background was about equally blurry. Feeling a bit confused, I tried turning of VR. Below is a 1:1 comparison with and without vibration reduction:

Pixels viewed at 1:1 while using a tripod, with and without vibration reduction.

I was surprised to find vibration reduction was make the shot worse. Lesson learned – turn off vibration reduction when using a tripod. It sounds like a feature you should never turn off, but apparently it was over-correcting for handheld vibrations which weren’t happening, since the camera was on a stationary object. I was using an older Nikon AF-S DX ED 18-55mm F3.5-5.6G lens, and it’s possible this issue is not as severe on newer VR II lens.

Comprehensive comparison of pore-scale models for multiphase flow in porous media

My phase-field simulation of viscous fingering in porous media.

A paper that I contributed simulations to was recently published in the journal PNAS. The contributors were asked to simulate the pore-scale oil/water displacement pattern in a radial Hele-Shaw cell with posts, under different injection rates and wettability conditions. Experimental data was provided and the idea was to compare the pros and cons of different modeling techniques. It was a challenging task.

I submitted phase-field results which were accurate for several of the cases, but like many techniques struggled with strong imbibition. I would like to point out one correction that never made it into the final paper. Fig. 4B shows my results, PF2, producing a very inaccurate finger width of Wf=93. This value was calculated from my original submission, which stopped well before the injected fluid reached the boundary. During revision I ran the simulation to completion (see results in supplementary information) which produced a finger width of Wf=20, close to the experimental value. Unfortunately I missed that Fig 4B was not updated with the correct Wf in the final revision, and the paper was published with the old value.