This reminded me of the time when a contributor to this forum attempted to browbeat me into accepting that SARS and the present Covid are one and the same thing:
At the time I referred to another article published in Nature, https://www.nature.com/articles/s41564-020-0695-z, which included the following quote:Covid-19 is SARS. Precisely, it's SARS-2, and killing at close to the same rate. It isn't MERS (a serious killer). And it isn't Ebola (pre-vaccine, lethal)
At the time I wrote:The Coronaviridae Study Group (CSG) of the International Committee on Taxonomy of Viruses, which is responsible for developing the classification of viruses and taxon nomenclature of the family Coronaviridae, has assessed the placement of the human pathogen, tentatively named 2019-nCoV, within the Coronaviridae. Based on phylogeny, taxonomy and established practice, the CSG recognizes this virus as forming a sister clade to the prototype human and bat severe acute respiratory syndrome coronaviruses (SARS-CoVs) of the species Severe acute respiratory syndrome-related coronavirus, and designates it as SARS-CoV-2.
This new article makes the point much more strongly. It uses a taxonomy in which SARS-CoV-1, and SARS-CoV-2 are not even strains within the same viral species, but within a sub-genus (thus still closely related, but not so closely as to be regarded as types of the one species).The key words here are "sister clade".
The relationship is thus: a species of coronaviruses which contains strains including the virus which caused SARS, a virus identified as being hosted in bats and this new virus which causes the disease, Covid-19.
Moreover, it concludes that the two viruses each have diverged from the parent horseshoe bat sarbecovirus population from 40 to 70 years ago, and last shared a common ancestor perhaps 800 years ago.
I hope this can put away this particular delusion, that SARS and Covid-19 are the same thing, for good.
(Although, it does make the worrying suggestion that there may be more human lethal virus mutations that can have arisen or may arise from the same sarbecovirus population.)