Thread by @trvrb

A brief update on our work with the sequencing of the White House #COVID19 outbreak. Since posting on Nov 1, groups from all over the US have shared an additional 2798 #SARSCOV2 viral genomes via @gisaid and additional connections have emerged. 1/9

https://twitter.com/trvrb/status/1323011782714159105

This sequencing has revealed additional viruses circulating in Virginia and collected between Aug and Oct that fall alongside the WH lineage, as well as three viruses from Michigan collected in Oct that are closely related to sequences from the White House outbreak. 2/9

These three viruses from Michigan possess 1 differentiating mutation and the two White House-associated viruses also possess 1 differentiating mutation. A molecular clock analysis places their common ancestor in Aug or Sep. Interactive figure at nextstrain.org/community/blab…. 3/9

It's unclear if these viruses from Michigan represent an offshoot of the transmission chain or if they represent the geographic line of descent. Additional sequencing may continue to shed light on these origins. At this point, it's still hard to say much. 4/9

In the last few days a second WH-related cluster has emerged with 17 publicly announced cases reported between Nov 4 and Nov 11 (whcovidtrack.com/chief-of-staff…). 5/9

Sequencing cases from this second cluster could immediately distinguish between:
1. Ongoing transmission in the WH network throughout October
2. A second unrelated introduction event
6/9

These two scenarios have important implications for ongoing infection control procedures. We'd be happy to work with anyone at the @WhiteHouse Medical Unit to sequence further cases from the outbreak. 7/9

Or if there are any individuals with COVID diagnoses who are connected to this outbreak who want to participate in a research study, please get in touch. We are required to keep identifiable information completely confidential. In this case, please contact [e-mail]. 8/9

Lastly, I'd like to thank the Virginia Division of Consolidated Laboratory Services, the University of Michigan Clinical Microbiology Laboratory and the @lauringlab at the University of Michigan for sharing viral genomic data. 9/9