Thread by @kakape

If you haven‘t noticed: After a lot of reporting on vaccine side effects and vaccine equity and a brief break, I‘m back on variant watch.
So let‘s start with a catch-up thread on all things #deltavariant and new story with @meredithwadman is here:
sciencemag.org/news/2021/06/d…

@meredithwadman The delta variant was first isolated in the Indian state of Maharashtra in December but really only got attention when it started to take off a couple of months later and when it rapidly spread in the UK.
So as usual: It’s early days and many things are still uncertain.

@meredithwadman This from @PHE_uk last week is still a great overview of where we are on the #DeltaVariant:
assets.publishing.service.gov.uk/government/upl…

@meredithwadman @PHE_uk On immune escape:
#deltavariant seems better at infecting people even though they have been immunised with AZ or Pfizer vaccine. The difference is biggest after just one dose.
Crucially, protection against hospitalization appears to be just as high as it was for Alpha.

@meredithwadman @PHE_uk The question, of course, is what the situation is for other vaccines and what the situation is for natural immunity from infection. That will be crucial data in the coming days and weeks...

@meredithwadman @PHE_uk Transmissibility:
Data seems clear by now that #deltavariant is more transmissible than alpha. Question is by how much and current estimates are around 50%.
That is a lot.
We have come a long way from the virus that originally sickened people in Wuhan.

@meredithwadman @PHE_uk As @ArisKatzourakis told me:
"If Alpha really is approximately 50% more transmissible than the wild type strain, and Delta is 50% more transmissible again than Alpha, we’re talking about a virus that’s more than twice as transmissible as the initial strain."

@meredithwadman @PHE_uk @ArisKatzourakis If the data bears this out, "that’s catastrophic news for the rest of the world”, @AdamJKucharski told me.
“My immediate worry is what will happen when Delta is introduced into Africa,” @doctorsoumya told me. “You could end up with explosive outbreaks.”

@meredithwadman @PHE_uk @ArisKatzourakis @AdamJKucharski @doctorsoumya So what needs to happen?
Same as always: Use non-pharmaceutical interventions to keep the virus from spreading while rushing to vaccinate the most vulnerable people in the whole world.
Vaccinating the world was always a race against time. And the clock is ticking faster now.

@meredithwadman @PHE_uk @ArisKatzourakis @AdamJKucharski @doctorsoumya Reducing the spread of #sarscov2 is also crucial to keep further variants from evolving.
“Anything that’s happened at least twice in evolution is part of a pattern,” @ArisKatzourakis told me. “I would be very unsurprised if we saw equivalent changes over the coming year or two.”