As reported by @CDCDirector, B.1.1.7 represents more than 50% of cases in US. And fraction still increasing.
See 7 states where Helix tests a lot. Details in 🧵
2/ Before going in details on B.1.1.7, here are some stats on vaccinations in US from @CDC. What an effort! I am very optimistic for the US.
Also important to note that all vaccines work very well against the B.1.1.7 variant. It is really incredible how well they work.
3/ California
Fraction of B.1.1.7 is still increasing. Numbers are small, but I think we may have enough information to look closely at direct competition between B.1.429 and B.1.1.7. Hypothesis is that B.1.1.7 is more transmissible.
4/
Quick note on SGTF
stands for S Gene Target Failure
Also called S Gene drop-out
When we do a PCR test, we look at S gene, N gene & ORF1a. B.1.1.7 variant has a deletion in S gene interfering with test leading to a positive signal in N & ORF1a targets, but not S target.
5/ Florida
Y-axis is different, but it is still clear that B.1.1.7 counts are growing steadily, while non-B.1.1.7 cases are now flattening (after a long decrease).
6/ Georgia
In our tests, one of the states with highest fraction of cases being B.1.1.7. Counts increasing, but slower than MI for example.
7/
Massachusetts
8/ Michigan
There is a lot of talk about MI. Because cases increasing fast. Counts below are pretty clear.
Looks like conditions start of Feb favored virus (as non-SGTF also started to rise), and B.1.1.7 took fully advantage of it.
Co-circultation of both variants
20 samples with co-infections
Evidence of a few recombinations in co-infections
& 2 infections with 100% recombinant
Details in 🧵
@shishiluo@my_helix 2/
Recombination is one way a virus can evolve. It allows to 'test' a new combination of mutations, which could provide an advantage or not.
@shishiluo@my_helix@edwardcholmes@SimonLoriereLab 3/
Lots of talk about Delta-Omicron possible recombinations because in worse case scenario, it could be a bad combo. But also simply because
- it was likely to happen de to co-circulation of both
&
- also easier to identify because of high number of unique mutations of each
To try to 'predict' what may happen in the USA in next couple of weeks, we can look what was the BA.1.1 situation in these countries before BA.2 took over.
2/
Screening an entire population is different than doing the exome to identify cause of a rare disorder.
3/
The goal is to select gene <-> disease combinations that look like the one on the right in graph (Disease Z)
A large fraction of carriers (of a genetic variant) will present the disease if nothing is done
& strong enrichment in carriers compared to non-carriers.