Two time capsules 100s of miles away have found something interesting for the hunt of origins of Covid-19. Scientists working on a frozen horseshoe bat specimen in Cambodia discovered a coronavirus which shared very similar characteristics with SARS-CoV-2.
In similar news, a research group in Japan working on frozen droppings collected from a horseshoe bat also came across a virus belonging to the corona family which was strikingly similar to SARS-CoV-2.
Researchers told @NatureNews they found a coronavirus closely related to SARS-CoV-2 in bats stored in a freezer in Cambodia. Another team in Japan reported the discovery of another closely related coronavirus — also found in frozen bat droppings. https://t.co/hG6aUKCNDO
— Nature News & Comment (@NatureNews) November 23, 2020
Since the beginning of this pandemic in China, WHO has been searching all across the world to try and identify the origin of Coronavirus and to back track the event which led to its jump from a horseshoe bat to humans. According to the report in nature, this is the first time that WHO has been successful in identifying a similar virus outside of mainland China.
It is also still unknown that if the virus came directly from the bats or was there another intermediary host. But still both these samples are yet to be sequenced completely before a final verdict can be given on its relation with the virus that causes SARS-CoV-2.
Once gene sequencing is complete and the relation of these viruses to SARS-CoV-2 is established it will help scientist to know how this virus infected the bats and how it got transmitted to humans. For such assumptions to hold any ground, scientists believe that the newly discovered virus from frozen specimens have to share at least 97% of their genetic material with SARS-CoV-2.
Even if the similarity is not at this high percentage still this could mean that these viruses are somewhat distantly related which will be helpful in predicting the trends in this particular family of viruses.
Another virus codenamed Rc-0319 was isolated and sequenced from a horseshoe bat which was captured in Japan in 2013. Genetic sequencing of Rc-0319 showed that it shared 81% genetic material with SARS-CoV-2 which is very similar but not enough for the scientists to connect dots that can lead them to the origin of this pandemic causing organism.
With the recent discoveries in Cambodia and Japan scientists are interested as it has more or less answered the question about the animal harboring SARS-CoV-2 which is horseshoe bat. This discovery also confirms that such viruses are found in horseshoe bats irrespective of the geographical location in which these bats were found.
These discoveries are also of interest because it means there are countless possibilities of such viruses being stored in other lab freezers all over the world. Scientists are interested to test these frozen mammals and other animals so that they can get a chance to study the antibodies which are created in these animals to help in harboring the virus while not allowing it become life threatening.
The nearest known related virus to SARS-CoV-2 is RaTG13 which is almost 96% similar but for a virus to be an immediate ancestor it has to be 99% similar to SARS-CoV-2.
In terms of evolutions, researchers are of the opinion that a four percent difference in similarity in the genomes of SARS-CoV-2 and RaTG13 means that these two were related as much as seventy years ago and since then they have diverged into different viruses. But interestingly both these virus get attached to the same receptor in order to gain access into mammalian cells.