We support the view that the Guangdong Pangolins are the intermediate hosts that adapted the SARS-CoV-2 and represented a significant evolutionary link.
https://pmc.ncbi.nlm.nih.gov/articles/PMC9408936/
. Although SARS-CoV-2 uses ACE-2, five of the six critical amino acid residues in the RBD
are different from those of SARS-CoV but identical to those of pangolin SARS-CoV, leading to speculation that the SARS-CoV-2 RBD may have arisen through recent recombination events in pangolins or that SARS-CoV-2 and pangolin SARS-CoVs represent the result of coevolution [45].
In reality, bats are rarely consumed in Central China, where market photos usually show Indonesia. The pangolin trade remains a major problem in other Chinese cities and shopping centers, but not in Wuhan.
https://www.allmultidisciplinaryjournal.com/uploads/archives/20251008124748_MGE-2025-5-143.1.pdf
70% of all diseases affecting humans originate in animals, such as avian flu, HIV, Ebola, and so on
...............
In a study by Xiao et al. (2020) [48], entitled “Isolation of SARS-CoV-2 related coronavirus from Malayan pangolins, ” and published in the prestigious journal Nature, they demonstrated that a coronavirus, called pangolin-CoV, isolated from a Malayan pangolin, exhibits 100%, 98.6%, 97.8%, and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N, and S proteins, respectively. Notably, the receptor-binding domain of the pangolin-CoV S protein is nearly identical to that of SARS-CoV-2, with one non-critical
amino acid difference. This comparative genomic analysis suggests that SARS-CoV-2 may have originated from the recombination of a pangolin-CoV-like virus with a RaTG13-
like virus. The pangolin-CoV virus was detected in 17 of the 25 Malayan pangolins analyzed. Infected pangolins showed clinical signs and histological changes, and circulating
antibodies against pangolin-CoV virus reacted with the S protein of SARS-CoV-2.
pangolins—the most trafficked mammal in the illegal wildlife trade—could pose a
future threat to public health if the wildlife...........
This wouldn't be the case with SARS-CoV-2, the virus that causes COVID-19. The phenomenon known as "zoonotic spillover" is when a pathogen/etiological agent passes from a wild/natural reservoir (bats and pangolins) to human............
https://www.oxfordstudent.com/2021/06/08/bats-and-pangolins-not-sold-at-wuhan-markets-says-oxford-research/
Research by Oxford's Wildlife Conservation Fellow, Professor David Macdonald, has shown that neither bats nor pangolins were sold at Wuhan's wet markets........
Pangolin trade is still a significant issue in other Chinese cities and
trading nodes, but not in Wuhan. What were there, however, were 47,381
individuals from 38 species, including 31 protected species, all kept in
dreadful conditions and teeming with all kinds of other infectious
diseases, ready to be slaughtered on demand, if not sold as pets.”
- Later,
more in-depth genomic analyses revealed that while similar, the
pangolin coronaviruses were not a perfect match to SARS-CoV-2 across the
entire genome and likely represented a parallel host infected by a
common ancestor virus.
- The
binding affinity of the pangolin ACE2 receptor for SARS-CoV-2 was also
later reported to be low, further casting doubt on it being the direct
intermediate.
- No firm conclusion has been drawn, and other potential intermediate hosts, such as raccoon dogs, are still being considered.
Ultimately,
the exact animal responsible for the jump to humans remains
unconfirmed, but the pangolin is considered a victim of illegal wildlife
trade rather than the primary culprit. The unsanitary conditions and
close proximity of diverse species in wildlife markets are widely
considered the human-driven factors that facilitate such zoonotic
disease transmission events.
