Scientists have been trying to find the real origin of the novel coronavirus that first infected a resident in Wuhan, China. Now, a team of researchers believe that they have found the missing link that carried the virus to humans.
Initial reports suggested that the virus that causes COVID-19 came from bats. However, scientists said it potentially needed another host to mutate and become strong enough to infect people.
One research claimed that snakes can be the intermediate hosts of the novel coronavirus. However, all known types of coronaviruses, like the one that caused SARS and MERS, infect only mammals and birds.
Another previous study showed that an HIV-1 protein had “uncanny similarities” with an important coronavirus protein. Researchers withdrew their paper due to scientific criticism.
However, the findings caused rumors and conspiracy theories that COVID-19 was caused by a virus that was engineered in a lab in Wuhan.
The latest study, published in Journal of Proteome Research, debunked the link between COVID-19, snakes and HIV. Researchers said pangolins are more likely the missing link that helped the virus move between bats and humans.
The findings come from the analysis of the novel coronavirus’ genome using new bioinformatics methods and large data sets. Researchers also collected DNA and protein sequences from pangolin tissues.
Comparing the virus present in the animal and humans, the team found that protein sequences in the lungs of infected pangolins were 91 percent identical to the proteins in humans with COVID-19.
The receptor binding domain of a spike protein, which helps the virus get into mammalian cells, from the coronavirus in pangolin appeared with only five amino acid differences from COVID-19 in people. However, bat viral proteins had 19 differences when paired to the human coronavirus.
“This evidence points to the pangolin as the most likely intermediate host for the new coronavirus,” the researchers said in a statement.
But the team noted more studies are required to confirm their findings. They said it could be possible that the novel coronavirus jumped from additional intermediate hosts before it went to humans.