As the world continues to struggle against the COVID-19 pandemic, scientists have been looking into the origin of the novel coronavirus SARS-CoV-2 and its chain of transmission leading up to humans. According to a recent study, pangolins may have played a role in the origin of the contagion that has infected over 4.1 million people worldwide.
SARS-CoV-2 is a zoonotic infection and has been traced to bats for its RaTG13 genome sequence but scientists have argued that the bat virus cannot directly infect humans, making the case for an intermediate host.
While earlier evidence has pointed towards pangolins, a recent study based on comparative genomic analysis can driving scientific consensus on the scaly anteater being the potential missing link in transmission between bat to humans.
As per the research paper, scientists from South China Agricultural University have isolated a coronavirus in Malayan pangolins that showed 100%, 98.6%, 97.8%, and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N and S genes, respectively.
The coronavirus, dubbed Pangolin-CoV, has been found to be 91.02% identical to SARS-CoV-2 at the whole-genome level, making it the closest relative of SARS-CoV-2 behind RaTG13. Pangolin-CoV was found to be particularly identical to Sars-CoV-2 in its receptor-binding domain (RBD) that consists of an amino acid fragment, which is responsible for recognising and binding the cell surface receptor.
The researchers studied 25 Malayan pangolins, of which Pangolin-CoV was detected in 17 specimens. The infected pangolins further showed clinical signs and histological changes while the circulating antibodies against Pangolin-CoV reacted with a protein strand of SARS-CoV-2.
The scientist also observed that pangolins are the most-trafficked mammal in the world and the novel coronavirus highlights a future threat to public health if wildlife trade is not controlled.
The COVID-19 pandemic saw it's patient zero in a 57-year-old shrimp seller at a wet market in China's Wuhan. Chinese wet markets are known to sell rare animals and suspected for underground wildlife trade.
In a big development two weeks back, China was reported to have passed regulations banning the hunting and consumption of wild animals and their products. The local newspaper stated that steps are being taken to safeguard people's health and livelihoods, adding that violators will be severely punished. The ban is expected to come into effect from June 1.