Thread by @DrEricDing

📍Bad news on #MuVariant—Japanese scientists: "Mu variant is highly resistant to sera from convalescent & [Pfizer]-vaccinated people. Direct comparison of different spike proteins revealed that Mu spike is more resistant…than all other current variants”🧵
biorxiv.org/content/10.110…

2) The #MuVariant started in Colombia 🇨🇴, but is already worldwide, including in US and UK. In Colombia, how fast did it dominate? Pretty fast. But #DeltaVariant is catch up with it too.

3) Where is it in UK? Popped up everywhere despite Delta domination. Hmm. the-sun.com/health/3614819…

4) The Mu coronavirus variant has been recorded in 49 US states, with Florida and California reporting the highest numbers of Mu infections. Also quite a lot in Alaska.

yahoo.com/entertainment/…

5) Only 1 per cent of Covid samples across the US contain the Mu variant, while the Delta variant represented 99 per cent of cases.

Mu is not an “immediate threat”, said Dr Anthony Fauci, in a news conference. But scientists will be “keeping a very close eye on it”.

6) “This variant has a constellation of mutations that suggests that it would evade certain antibodies, not only monoclonal antibodies, but vaccine- and convalescent serum-induced antibodies,” Fauci said.

7) My take—While Mu is more resistant to antibodies, it may not spread as fast, since contagiousness / transmissibility is not same as antibody resistance. Delta is still king worldwide… but what I am watching out for is signs if Mu makes inroads or not in any country over Delta

8) The @WHO agrees the #MuVariant needs attention. They warned about it last week as a new variant of interest and admit it has “potential to evade immunity" from previous infection or vaccination, says WHO

9) More on #MuVariant in South America - it increased in S. America earlier than Delta. Hence its seems to have a small foothold.

nextstrain.org/ncov/gisaid/so…

10) But #MuVariant is slightly slowing in S America, while Delta is expanding. But it is still variable by country.

11) That said, since #MuVariant seems to be more evasive against both vaccines (7x neutralization drop) & evasive against natural infection (12x drop)— as more are exposed, #MuVariant might be more competitive over time as variants that can “pole vault better” have a better edge.

12) But there is no guarantee- it could fall flat against Delta or fall flat against a 3rd booster shot if roll out is fast. The more we vaccinate the higher the poll vault height in which an evasive variant must ascend over. And that’s why mass vaccinations and boosters are key!

13) Mu’s growth doesn’t look that bad in the current PHE data. But keep in mind that each variant’s growth is versus other variants of its same time period of emergence. Other variants competed with non-Delta. Only Mu is competing against Delta - the heavy weight champion.

14) We need to prepare for the long haul. Delta won’t be the last VOC. #MuVariant sounds like it is worrying WHO too. But we must prepare for and surge other strategies besides vaccinations. We need ventilation most of all plus masks.

15) We need to reconsider massive gatherings and to improve indoor building ventilation…