And then there were two.

This week the FDA issued a EUA for Moderna's mRNA vaccine. Similar to Pfizer, the vaccine was 95% effective. Both Moderna and Pfizer are some of the most effective vaccines we have. As the comic XKCD put it, "Statistics tip: always try to get data that' good enough that you don't need to do statistics on it."

When people came in for their second shot, the Moderna team swabbed everyone to see if they had been infected with Covid; Pfizer did not do this test. What Moderna found was that even after one shot that it seemed to impart sterilizing immunity! This is a huge deal and will significantly reduce the spread.

The Moderna vaccine is a two-shot vaccine, but it can be kept at normal freezer temperatures, significantly easing distribution. Injections start today for Moderna.

We also discovered that Pfizer had underestimated how many doses we could get per vial! Bonus doses! Possible up to 40% more! Basically, if you want to guarantee that there is at least a certain amount per vial, you'll always be over. Different needles/practices can take more, but in this case, it looks like we'll normalize on treating it like the precious thing it is.

Unsurprisingly there have been some bumps in the road in the distribution. Operation Warp Speed had a test database from a few weeks ago that hadn't been updated, and many states thought they were getting more doses this week than they were.

Stanford manages to continue to destroy its reputation as a good medical establishment. They allocated almost none of the first 5,000 doses to the front line, going instead to senior people who don't even come into the hospital. Being the feckless cowards they are, the administrators blamed it on an algorithm. Algorithms aren't magic; they are human biases encoded into silicon; someone designed them and chose to use them. Do better.

Overall I'm happy with how the first week went, and it will get better as hospitals settle into a rhythm around it.

Pfizer says it plans to start trials for its vaccine in 5-11 year olds in April 2021, after compiling data from trials in 12-15 year olds. I expect by the fall, we will have vaccines for most ages.

This week the FDA also approved more at-home tests, which is great news. As the vaccines are rolled out, the ability to crush the remaining parts of the spread through rapid testing will be key.

As vaccines are rolled out, the question of priority has become of high interest. Lots of laypeople are arguing, and it resembles a freshman year philosophy class on the internet. The Advisory Committee on Immunization Practice [ACIP] is the body that sets the guidelines. It's filled with medical professionals and bioethicists who have spent their lives studying this question.

It's not an easy one; whatever they choose will result in the deaths of the population that didn't get prioritized. Worse yet, a later analysis might show that more lives could have been saved if they had done it differently.  They are keenly aware of this and doing their best to take all the data to make the best decision, now is not the time to harass them.

In the last 48 hours, reports have emerged that the might be a new, more infectious variant of Covid on the loose in London. It's still very early in the analysis, so no firm conclusions have been drawn. There is some, still unconfirmed, evidence that this variant is more transmissible but has not yet been shown to change the lethality of Covid. There is no data one way or the other to suggest that the vaccines that have been developed will or won't work, though scientists I follow believe it is unlikely to affect our current vaccines.

There's nothing to panic about right now. One reason it's hard to say if it's more infectious is that Covid cases have been spiking all over the US and Europe as winter has set in. Videos from last night in London show standing room only commuter trains going out of town, new variant or not that's going to cause massive spread.

Another reason it's hard to know much right now is the surveillance systems for genetic variants aren't comparable from country to county. The UK has one of the most advanced collection and sequencing operations on the planet. Even if the new variant wasn't more contagious, it could appear like it was given their current outbreak.

Viruses are always going to mutate. Covid has a much slower mutation rate than the flu, which is why vaccines will likely be extremely effective. There is a chance we'll need a new shot for Covid every few years.

The takeaway is that even if this variant is more contagious, it doesn't really change our approach. Masks and limiting indoor gathers are still the best way to fight it. The vaccine rollout will continue, and over time the fewer people have active Covid, the less mutation we'll see.

Even if the worst case happens, that our current vaccines don't work on the new variant, we are so much better prepared to do a turn on a new vaccine. We set the speed record for the current Covid strain. If we had to do it again, we'd set the record again.

Take a breath. Immunity is on its way. Over 250,000 people got their first dose this week; next week, it'll be more.

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