I wanted to pass on, and briefly comment on, a few pieces of COVID-19 news and science I saw recently. One particularly notable item was on the apparent effectiveness of masks to prevent infection; the CDC is reporting on two hairstylists who got COVID-19 and then worked with 139 customers and none got COVID-19. Yet even an (unmasked) asymptomatic person in an elevator can spread COVID-19. Back in March, I didn’t understand that the point of masks is to protect others, but that’s definitely had time to sink in now, and stories like this drive it home.

I also saw this article back in June on when epidemiologists expect to do things again – the NY Times got 511 epidemiologists to weigh in on when they expect to resume certain normal activities. The results are roughly in line with what I expected, but some may find them surprising and it’s worth a quick look.

Updates on vaccine progress

This week also brought some news on two of the leading vaccine candidates – from Moderna and Pfizer (though there is a ton going on in this space generally; it’s going to be a busy fall for science). Derek Lowe, a leading pharma industry blogger, explained the news at a level which is relatively accessible to a layperson. The Moderna vaccine is still progressing and results are roughly as encouraging as they could be/ought to be at this point.

On the Pfizer front, the article was less about news and more about an interview and gives you a bit of a window into what’s going on. Pfizer is really pushing on this – as are many others in the industry – not in an attempt to get rich but to save lives. (The cynical might remark that they probably also see it as an advertising opportunity, which is probably true – but they’re pouring tons of money into it on a big gamble.) Anyway, the article is worth a quick read.

What about reinfections? Q&A and some news

I’ve seen a few articles here and there about people getting COVID-19 more than once; for example, today there was one about a Nashville photographer who got it more than once. My understanding is that we learn relatively little from this about whether COVID-19 immunity will in general be long-lasting, as immune response varies person to person. Here’s what I wrote on Facebook in an attempt to explain:

“Can get” and “is normal to be able to get” are very different things. All the good data we have so far indicates that immune response to this is normal and that many people should be (and probably are) protected afterwards, probably for a good length of time. But the immune system is not an exact thing; it’s a very general protective system which varies from person to person and is designed to respond to outside threats in an innovative way, so individual responses vary. I think this is very consistent with a picture where a small fraction of people might be able to be reinfected (or as the article itself mentions, the virus might just have gone dormant and come back).

There’s a ton of science here which is still unresolved. But anecdotal reports of someone getting it twice don’t really contribute to us resolving that science, as such reports are very consistent with normal immune response as I understand it.

TL/DR: Biology is complicated and anything can happen. But for MOST people, our best data so far indicates immune response to COVID-19 should be normal and most people will not be able to be reinfected.

Someone followed up by asking about data which shows antibody counts decrease over time following exposure (you’ll see some of that same kind of data in the Moderna vaccine article I noted above), so I wrote this in response:

Antibodies do [go down over time], but the immune response is not solely a function of antibodies. Specifically, your immune system basically tries to hang on to some number of antibodies to recognize everything it has ever seen before as sort of a “recipe”. Then when it finds it has antibodies to recognize an invader that are helpful it quickly ramps up production. So, (a) antibodies are expected to go down over time, but (b) what’s critical is how long the immune protection actually lasts, and this doesn’t necessarily relate directly to antibody count. People MEASURE antibody count because it’s easy to measure, but what that actually means for reinfection is anyone’s guess at this point.

To really find out how antibody count/type of antibodies/etc relate to COVID protection, we need to … actually test it. But I’m sure you can imagine people are likely not eager to sign up for that test, and most science agencies would not approve running such tests.

In other words, we will probably only find out what antibody counts mean for protection against infections when we begin running large scale vaccine clinical trials this fall.

RECENT NEWS GIVES US MORE INSIGHT ON THIS: I wrote the above before this recent news on immune response. Basically, it seems scientists were doing the next best thing relative to testing how people respond to “SARS CoV-2” reinfection (that’s COVID-19 reinfection, but SARS CoV-2 is the name of the virus) – instead of giving people the virus again, they’re taking crucial immune system cells (T cells) from people who have had the virus and seeing how they respond to proteins from the virus. This is better than testing antibody counts; as I mentioned above, antibody counts are easy to measure (and may go down with time), but what actually matters is how the immune system responds to the virus. T cells are a key part of that.

So in this work, instead of looking at antibody counts, researchers looked at T cell response to viral proteins. What they find is that these cells do react to SARS CoV-2 proteins, suggesting they may be protective against infection. Also, they looked at response to the original SARS (from years ago) and folks still have T-cell response 17 years later! And, these T cells react against (and perhaps provide protection against?) SARS CoV-2, which cause COVID-19 even though they have never seen it before, and have only seen the original SARS.

Also, and perhaps even more interestingly, T cells from some people who have not been exposed to either SARS or SARS CoV-2 have response against both. So maybe there has been some other virus previously that helped some people’s T-cells react against these viruses.

Anyway, on the whole this is encouraging news for vaccine development and COVID-19 immune response in general. There are still a lot of things we don’t know, but at least now we can see a bit beyond antibody counts and we indeed know that T-cell response to SARS viruses (like the one causing COVID-19) can stick around for decades. This suggests that many people will end up with long-lasting protection. It doesn’t prove it, of course, because naturally the researchers didn’t try to infect their patients again – but it’s suggestive and the best we have to work with for now.

A second wave of deaths is coming in the US

Several people posted this article from the Atlantic on a second surge of deaths in the US; it’s a fairly good summary of where we currently stand and seem to be headed, so if you’re not up on that it’s a good read.

What stood out to me more about it, though, was some of the raw stats out of New York City:

New York City has lost 23,353 lives. That’s 0.28 percent of the city’s population. If, as some antibody-prevalence surveys suggest, 20 percent of New Yorkers were infected, that’s an infection-fatality rate of more than 1.3 percent, which exceeds what the CDC or anyone else is planning for. To put it in the same terms discussed here, New York City saw 2,780 deaths per million people. A similar scenario across the South and West would kill over 550,000 more Americans in just a few months, moving the country to 680,000 dead

So, 0.28 percent of New York City’s population died. I suppose as a percentage that doesn’t sound that high, but my church is 400+ people, so if we had NYC-level illness in my church (for example) I could expect to lose someone I know, or more. And that’s not counting people I work with, etc., nor is it considering the possibility that more than 20% of a group of people could get it.

So, I’m continuing to wear a mask and spend little time in public places except when necessary. Along those same lines, apparently the CDC is now saying that we’d have this under control in 4-6 weeks if everyone wears masks. I think this – and vaccine development – is our best shot in the coming few weeks and months.

As a Christian, I trust God and I know my future is secure in his hands. But I don’t wear a mask to keep myself safe. I wear a mask to protect others.