WIV, EcoHealth, the Mojiang ‘miners’ cases and a bat sampling trip in April 2012

Gilles Demaneuf
12 min readSep 25, 2020

Research by DRASTIC, a group of researchers working together to investigate the origins of SARS-COV-2, starting from facts and not bending to any pressure. DRASTIC members were the first ones to discover the Mojiang ‘miners’ story.


What exactly happened at the Mojiang mine in April 2012 is important. It is in that mine that RaTG13 (aka. BatCov/4991) — the closest known relative to SARS-CoV-2 — was sampled in 2013 by the WIV virus hunters.

The story around RaTG13 is itself rather confusing, but we will not delve into this here (see instead [1, 2] for some analysis). Here we simply try to elucidate what exactly happened in that mine at the time and ask some important questions.

The medical cases of the 6 workers clearing guano from the Mojiang mine:

From the MS Thesis by Li Xu, we know that workers started removing bat guano from the Mojiang abandoned copper mine on the 2nd April 2012. No reason for their work is given.The first batch of 4 workers started on Monday the 2nd April for a 2 week period (to Friday the 16th April). They were all middle-aged (42, 45, 46, 63). They all started experiencing symptoms between the 10th and 16th April.

The 2nd batch of 2 workers started on Sunday the 22nd April (possibly for a night shift). They stopped on Thursday the 26th when one is admitted to Kun Ming hospital. That batch was made up of much younger men (30 and 32) than the first batch. When the second batch started on the 22nd, the first batch had already experienced symptoms.

5 of the 6 workers are recorded as having first sought local treatment. Somehow all 6 workers ended up at Kun Ming medical university hospital. Soon the Emergency Department would raise the alarm. As the MS Thesis states:

After 5 patients were admitted to our department (Wu XX was admitted to our Hospital Respiratory Department), the on-duty doctor immediately reported the specific situation to the medical affairs department to prevent the outbreak and epidemic of infectious diseases.
[original and translation] Note: The admission date would have been the 2nd May 2012. The medical affairs departments is basically the local CDC.

Dr. Xie Can Mao (Chief Physician, Respiratory department of Institute of Respiratory Disease of the 1st Affiliated hospital of Sun Yat-Sen University, Guangzhou, Guangdong province) did a remote consultation on the 4th June, about a month after the death of patient #1 and a week after the release of patient #5 and #6, and while patients #2, #3 and #4 where still in hospital (with patient #2 doing rather badly). He diagnosed a possible fungal infection for patients #2, #3 and #4 through remote meetings (histoplasmosis?).

Initially various etiology tests (swabs and blood) were performed on patients Guo and Liu by the Chengdu Military Region Centre for Disease Control and Prevention (成 都 军 区 疾 病 预 防 控 制 中 心, a CDC branch located in Kun Ming), and came back all negative for a SARS-CoV infection.

A week after patient #2 died on the 12th June, Dr Zhong Nan Shan (the top SARS specialist in China, known for being outspoken, also Respiratory department of Institute of Respiratory Disease of the 1st Affiliated hospital of Sun Yat-Sen University, Guangzhou, Guangdong province) was initially consulted on the 19th June. He would then help handle the cases of the two patients remaining in hospital (patients #3 and #4, while the two young patients who were admitted last had recovered in May). He quickly came to suspect a SARS-like infection and got the two remaining patients and the two recovered ones to be tested again for SARS antibodies. The WIV handled these tests which all turned out positive.

These WIV tests included positive tests for patient Guo and Liu (#3 and #4), which previously had returned negative tests with the Chengdu Military Region CDC. It would have been interesting to also have the WIV retest the samples of Guo and Liu (swabs and blood) used with the Chengdu Military Region CDC, but this is not mentioned.

Eventually 3 workers would die. The families of all 3 refused an autopsy, possibly because of the animist beliefs of the Mojiang Hani people.

Summary of the workers’ cases

(If necessary, use this link for a clearer image)

Timeline of events

(if necessary, use this link for a clearer image)


Conflicting conclusions:

Under the guidance of SARS expert Dr Zhong Nan Shan, the MS Thesis states that:

Based on the above mentioned cases and related researches, the unknown virus that lead to severe pneumonia could be: The SARS-like-CoV from the Chinese rufous horseshoe bat or another Bats SARS-like CoV.

The MS Thesis then explicitly mentions that:

A paper published in Science magazine in 2005 by Scientist Shi Zheng Li and Zhang Shu Yi from Wuhan Institute of Virology under Chinese Academy of Science, concluded that the SARS-like-CoV carried by bats is not contagious to humans. This contradiction indicates the importance of these six cases.

and it further recommends that:

Given all of the six patients were exposed to huge amounts of bats and their feces, also inhaling the dust of the feces, it is important to go sampling the live bats and their feces in the same cave.

However the 2016 PhD thesis under the guidance of Gao Fu, China CDC head, instead concludes 4 years after the publication of the MS Thesis that:

Therefore the cause of the outbreak is not yet clear. Despite the efforts of many parties, it has become an unsolved case so far.

This is a very odd conclusion.

  • It totally ignores the opinion and diagnostic of the top expert in the field, Dr Zhong Nan Shan.
  • It also totally ignores the 4 SARS antibodies test done at the WIV that all turned out positive (see PhD thesis, 3.3 Discussion).
  • It further ignores the fact that the WIV did indeed follow the lead of Dr Zhong Nan Shan and went sampling bats in that very cave in 2013.
  • Last it ignores the very finding of the WIV researchers themselves (including Shi Zheng Li) that disclosed in a 2013 Nature paper that horseshoe bats from around Kun Ming (Yunnan) — that they sampled between April 2011 and September 2012 — indeed had the potential to directly infect humans. This key paper was followed by an important Nature paper in 2015 which concluded that there is ‘a potential risk of SARS-CoV re-emergence from viruses currently circulating in bat populations’, based on a SARS receptor experiment using a chimeric virus.

Note: A viral infection is to this day considered a much more likely cause of the deaths of the workers than a fungal infection. What is striking though is the strong reluctance of the WIV to consider a BatCov infection, even years after. In contrast, in the context of Covid19 the official narrative backed by the WIV is that BatCov spillovers happen all the time and have a potential for community outbreaks. Rather striking too is that EcoHealth itself published some article and simulations soon after highlighting the risk of BatCov pandemics from bat guano collection spillovers (with no mention of the Mojiang cases).

The April 2012 Sampling trips:

EcoHealth + WIV collected many samples (a few 100s) from bats on sites not far from Mojiang in April 2012.

Sampling sites from Genbank and references in a paper. Using some clues related to bat species and locations given in section 3.1 of Yuan et al. (2014), combined with collection dates from Genbank, one can assert that the WIV and EcoHealth were a few hours by road from the Mojiang mine in:

  • Yuanjiang: 07-Apr-12
  • Mengla — Xishuangbanna Botanical Garden: 11-Apr-12, 15-Apr-12, 16-Apr-12 [3]
  • Mengla — Natural Arch: 18-Apr-12

Sampling sites from PREDICT website. If EcoHealth is present, the samplings are typically registered under the PREDICT program and some data is available on data.predict.global.

Here is the PREDICT map:

The position highlighted on the map (which is in Mojiang and about 30km in direct line from the abandoned mine) does not match any known bats sampling site in Mojiang. At the same time the Mengla samplings for April 2012 are correctly recorded, but there is no Yuanjiang data for April. There is however data recorded for a previous trip in Dec 2010 and shown in the right location on the map for Yuanjiang. This is rather confusing, but it could be that data.predict.global just did not record the Yuanjiang April 2012 samplings in the right place on the map, putting it in Mojiang instead of Yuanjiang. Still the samples listed on data.predict.global for that odd location do not match the data from Yuan et al. (2014) and Genbank, which in turn could just be a problem with incomplete data being recorded.

Summary on sampling sites: This summary map shows the starting point of the April 2012 sampling trip in Yuanjiang and the end point in Mengla. Mojiang is directly on the shortest route between these two points, and the abandoned mine only a short detour away.

Sampling Trips

Map showing April 2012 EcoHealth + WIV Sampling trips
available at https://goo.gl/maps/oZp2CzDV1QF8o9QD6


  • Available GPS coordinates for all points, except for odd Mojiang sampling location given by data.predict.global (approximate ~23.35N, 101.5716E based on PREDICT map above).
  • The Mojiang mine itself is at 23° 10' 36"N, 101° 21' 28"E. The mine was derelict and abandoned. It is also known as the Bengping copper mine (蚌坪銅礦). It seems to have been a rudimentary setup at its peak during the Great Leap Forward when a few thousand people were sent to work there with minimal equipment, producing only around 75t of copper per year.

The hospital trips:

Somehow the 6 rural workers all ended up in the same Kun Ming hospital, around the same date for the first 4, and despite different heath states at admission.

Here is the hospital trip that all the workers went on:

First affiliated hospital of Kun Ming Medical University, 348km from the abandoned mine

Here are maps showing alternative hospital trips from the Mojiang mine:

Puer’s People Hospital — 111km from the abandoned mine

Yuxi no2 People’s Hospital — 249km from the abandoned mine

Some questions:

  • Why did the 6 rural patients all end up in Kun Ming hospital (350km from the Mojiang mine) when there are hospitals in Yuxi on the way to Kun Ming but only 250 km away, or in Puer city only 111km away?
  • How could these two batches of admissions in the same distant hospital — all around the 26th April for the first 4 patients, and irrespective of the patients medical states (4 were in bad health on arrival, the 2 younger ones were not that bad) — happen without some form of coordination?
  • Concerning patient #6, the MS Thesis states that: ‘He went to the local hospital for treatment but no documentation. His symptoms had improved but wanted further treatment’. The MS Thesis further gives his initial physical examination which is not that bad (only the CT scan revealed a pulmonary infection). What happened to his documentation at the local hospital? Why did he bother travelling 350km if already improving and actually not doing badly when there were hospitals much closer?
  • Shouldn’t we expect that potentially more workers were working in the abandoned mine if the 6 admissions at the distant Kun Ming hospital were just coincidences?
  • What happened to the ‘possible epidemics outbreak’ report of the medical officer in charge of the Emergency Department of Kun Ming hospital, filed with the medical affair department on the arrival of the 5th patient there? What did the local CDC office do with it?
  • Why did the initial SARS-CoV tests done for patients Guo and Liu (by the Kun Ming-based Chengdu Military Region Centre for Disease Control and Prevention) return negative, when later the SARS-CoV tests on the same patients done by the WIV at the instigation of Dr Zhong Man Shan returned positive?
  • Why did the CDC and the WIV ignore the strong opinion of top SARS specialist Dr Zhong Nan Shan about the likely infection by a BatCov — and this for years following the MS Thesis publication — despite (1) the positive SARS antibodies tests of four workers done at the WIV, and (2) the very own published research of the VIW that soon demonstrated that direct bat-human infection by a BatCoV was possible?
  • Why did EcoHealth never mention the Mojiang cases in their assessment of potential pandemic risk from bat guano collection, or in the related 2013 paper, based on previous work at the famous Khao Chong Phran cave?
  • Why is http://data.predict.global not showing correct sampling sites for Apr 2012 ?
  • Why were these workers clearing out guano 150m deep into the abandoned mine?
  • Who employed these workers?
  • Were the workers possibly employed to prepare the mine for bat sampling within the cave?
  • What is typically the local CDC office involvement with site preparation and guidance of sampling teams to the sampling sites?
  • Did EcoHealth and/or the WIV sample, or intend to sample, at the Mojiang abandoned mine in April 2012?
  • Why did the second batch of workers consist of much younger workers than the first batch, after the first batch fell ill?

Post Scriptum:

Following the publication of this article, we became aware of an important publication by a small team lead by some conservation biologists from Xishuangbanna Botanical Garden, which was the last sampling site during that Apr 2012 sampling trip.

The paper [3] was published on the 21st Feb 2020 on a Chinese pre-print site. It is remarquable as:

  • It is the first article to systematically reject the wet-market hypothesis based on a careful analysis of available sequences to that date.
  • It tried to unravel the evolutionary links between Covid-19 and RaTG13, the virus that likely killed the non-miners.
  • It complained about the sequences for early cases not being published, which would greatly help understand the early evolution of the virus.
  • It clearly stated that the breakout may have started in November, not with the official December cases.

But even more importantly it was written by some of the most unlikely scientists:

  • Yu, Wen-Bin was and still is a conservation biologist at the Xishuangbanna Botanical Garden with a focus on botany
  • Tang, Guang-Da was at the time a conservation biologist from Shaogan University
  • Zhang, Li was a scientist from the Chinese Institute for Brain Research (Beijing). The only one with a strong genomics background,
  • Corlett, Richard T was and still is a Cambridge-educated senior conservation biologist at the Xishuangbanna Botanical Garden (since July 2012), with a wide expertise including climate change.

This unlikely group of scientists found it necessary to investigate a subject which had nothing at all to do with their field, and to invest their time in it so as to publish early on a Chinese pre-print site an article which main conclusions and questions have been fully validated since then,
Somehow two of them are related to the Xishuangbanna Botanical Garden, which was on the 2012 sampling trip.


  1. Jonathan Latham, Allison Wilson. ‘A Proposed Origin For SARS-CoV-2 And The COVID-19 Pandemic’. Aug 2020. Available at: https://www.scoop.co.nz/stories/SC2008/S00025/a-proposed-origin-for-sars-cov-2-and-the-covid-19-pandemic.htm
  2. Rahalkar MC, Bahulikar RA, ‘The Origin of ‘BatCoVRaTG13’, a Virus Closest to SARS-CoV-2'. Available at: https://doi.org/10.20944/preprints202005.0322.v1.
  3. For a very interesting paper coming out of Mengla, see preprint on 21 Feb 2020: http://chinaxiv.org/abs/202002.00033, final paper in May 2020: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7231477/. That paper, surprisingly written by conservation biologists, was the first paper to systematically refute the wet market hypothesis. It also concluded that the breakout would have started quite likely in late November and pointed to the need to publish more sequences from early cases to be able to understand the link between RATG13 and SARS-CoV-2.



Gilles Demaneuf

Opinions, analyses and views expressed are purely mine and should not in any way be characterised as representing any institution.