August 24, 2020 By Michael D. Shaw @ HealthNewsDigest
As the COVID-19 pandemic is hopefully winding down, the search
continues for a credible origin story of SARS-CoV-2, the viral cause of
the disease. Last week, we discussed how gain-of-function
research on related bat SARS-like viruses could have led to an
engineered pathogen, that was accidentally released from a Wuhan Lab.
After all, back in 2005,
Wuhan-based virologist Shi Zhengli, the “Bat Woman,” identified dozens
of deadly SARS-like coronaviruses that were found in samples of bat
droppings that Shi and her team collected in caves. One of those samples
contained a viral genome that is 96% identical to SARS-CoV-2. The
droppings, called “guano,” are highly-prized as a fertilizer. As such, the bat caves of China are worked heavily by guano miners.
Fast
forward to April, 2012. Six miners were working in an abandoned mine
shaft at the Mojiang mine in China’s Yunnan province that was loaded
with bat guano, along with a fungus that had built up on it. These men
became ill, and three eventually died. In his May, 2013 master’s thesis,
the treating physician, Li Xu, described their symptoms: high fever, a
dry cough, sore limbs and, in some cases, headaches. Notably these are all associated with COVID-19.
And, the miners were treated with ventilation; and an assortment of
drugs including steroids, blood thinners, and antibiotics—which also
parallels current COVID-19 treatment modalities.
These findings were released once virologist Jonathan Latham and molecular biologist Allison Wilson, of the non-profit Bioscience Resource Project in Ithaca, NY, translated Li’s thesis, posting it here.
While
attempting to do patient work-ups, and determine a course of treatment,
Li consulted with many specialists, including pulmonologist Zhong Nanshan,
a beloved scientist, who managed the SARS outbreak in 2003. Latham and
Wilson note that bringing in Zhong is significant, since it implies that
the illnesses of these miners were of great concern, and a SARS-like
virus was being considered as a cause.
Li also sent tissue samples to the Wuhan Institute of Virology—home of the “Bat Woman”—for testing. According to a Scientific American
article from June, she explained that the miners died from a fungal
infection, although it would have been only a matter of time before they
caught the coronaviruses if the mine had not been promptly shut down.
Among
other interesting points, the Li thesis notes that the immune systems
of the miners were compromised and remained so even for those
discharged. This weakness may also have encouraged evolution of the
virus. Moreover, unlike typical coronaviruses that typically run their
course in 10-14 days, at least two of the surviving miners suffered from
the illness for over four months.
In their presentation of Li’s
paper, Latham and Wilson raise some questions: Why did Bat Woman Shi’s
lab not acknowledge the miners’ deaths in any paper describing samples
taken from the mine? There were five scientific publications that very
early in the pandemic reported whole genome sequences for SARS-CoV-2.
Yet, only one of these
succeeded in identifying the most closely related viral sequence by
far: BtCoV/4991, a viral sequence in the possession of the Shi lab that
differed from SARS-CoV-2 by just five nucleotides.
The work and conclusions of Latham and Wilson have been praised by experts in the field, including George Church and Stuart Newman, who referred to it as “the best sourced explanation yet of the origins of SARS-CoV-2.”
Excellent work, but any way you slice it, all roads still lead back to China.
No comments:
Post a Comment