Thread by @Vaccinologist

A #thread on the origin of the Severe Acute Respiratory Syndrome #coronavirus-2 #SARSCoV2, the #virus causing #COVID19. SARS-CoV-2 was identified early January 2020; genetic sequence shared publicly on 11 January. #scicomm [image 감사합니다 @IBS_media] @Virologist_11 @dirgarambe

Full genetic sequence of #SARSCoV2 from early human cases & sequences of other virus isolated from human cases from China & all over the world since then show that SARS-CoV-2 has an ecological origin in #bats.

All available evidence to date suggests that #SARSCoV2 #coronavirus has a natural animal origin and is not a manipulated or constructed virus. nature.com/articles/s4159…

Many researchers have been able to look at the genomic features of #SARSCoV2 and have found that evidence does NOT support that SARS-CoV-2 is a laboratory construct. If it were a constructed virus, its genomic sequence would show a mix of known elements. This is not the case.

#SARSCoV1, the cause of the #SARS #outbreak in 2003, was also closely related to #coronaviruses isolated from #bats. The close genetic relations of SARS-CoV-1, SARSCoV-2 & other coronaviruses, suggest they all have ecological origin in bats.

https://twitter.com/Vaccinologist/status/1252890718084923393

Many of these #coronaviruses can also infect several other animal species. #SARSCoV infected civet cats & then humans, while #MERSCoV is found in dromedary #camels, and has continued to infect humans since 2012. All available evidence suggests #SARSCoV2 has a zoonotic source.

All published genetic sequences of #SARSCoV2 isolated from humans are very similar. This suggests that the start of the #outbreak resulted from a single point introduction in the human population around the time that the #virus was 1st reported in humans in #Wuhan (December 2019)

Currently, investigations are underway in China or planned to better understand the #outbreak source including investigations of human cases with symptom onset in & around #Wuhan in late 2019, environmental sampling from markets / farms where the 1st human cases were identified.