Good morning and welcome to COVID Transmissions.
It has been 428 days since the first documented human case of COVID-19.
Today we have an update on the deaths in Norway and some responses to reader comments. One comment shares an article that is generating a lot of pushback from vaccinologists and virologists, so I gave that a lengthy reply that should help clear things up.
As usual, bolded terms are linked to the running newsletter glossary.
Keep the newsletter growing by sharing it! I love talking about science and explaining important concepts in human health, but I rely on all of you to grow the audience for this:
Now, let’s talk COVID.
US passes 24 million cases of COVID-19
That’s not very good news, but I also don’t have much to say about it. Nationally the situation is bad. If you live in the US, please pay close attention to local advisories.
Update on post-vaccine deaths in Norway
Hours after yesterday’s newsletter went out, it was announced that the post-vaccination deaths in Norway could not be directly connected with the administration of the vaccine. This is a walk-back of earlier reports that indicated that some of these deaths may have been vaccine-related. Bloomberg covered this here: https://www.bloomberg.com/news/articles/2021-01-18/norway-finds-no-direct-link-between-elderly-deaths-and-vaccine
As discussed yesterday, these were already seriously ill patients. While it’s possible that the vaccine might have had an impact on their underlying condition, it appears that it is ultimately that underlying condition that brought about their deaths.
Not a fun news item either, but I do find this reassuring with regard to overall vaccine safety.
Biden plan for vaccination programs
Joe Biden, incoming US President, has outline a series of moves that he hopes will get the bumpy national vaccine rollout back on track.
He will be utilizing FEMA and other federal government agencies and resources to expand US infrastructure and operational capacity for vaccination. I hope this will help.
CIDRAP has additional details: https://www.cidrap.umn.edu/news-perspective/2021/01/biden-details-5-step-covid-vaccine-plan-names-new-lead-vaccines
What am I doing to cope with the pandemic? This:
The sea shanty fad, COVID-19 edition
You might have heard—and might not, for that matter—that there is a fad of performing sea shanties going on on TikTok right now.
Apparently, someone had the brilliance to combine this trend with COVID-19, and produced this:
TikTok embeds don’t work on substack, so that’s a tweet from the creator. What a rich media environment we live in. Enjoy!
A reader named Margaret left a comment linking to a news item that has made quite a splash in vaccine communications circles, largely because it is very inaccurate:
The New York Times morning briefing quoted a New England Journal of Medicine vaccine FAQ (https://www.nejm.org/covid-vaccine/faq): “If there is an example of a vaccine in widespread clinical use that has this selective effect — prevents disease but not infection — I can’t think of one!"
That doesn't match my understanding from what you've said here. Can you think of any examples of vaccines that prevent disease without providing sterilizing immunity? If not, what is it about SARS-CoV-2 that makes you think our priors from previous vaccines might not apply?
The article linked here is just wrong, and is generating a lot of pushback. I believe that NEJM should retract it or correct it. Here was my reply:
I find Dr. Sax's answer on this--and the fact that it appeared in the NEJM without being corrected--very puzzling, because it's wrong. Pretty much every virologist who has seen that claim has been scratching their heads about it because numerous vaccines in routine clinical use have disease-attenuating effects without providing sterilizing immunity. I've seen a couple of Twitter threads about this today, because of how incorrect it seems to be.
For example, the influenza virus vaccine *can* provide protection from infection, but it doesn't always. However, even if it does not provide protection from infection it is known to provide a spectrum of protection from disease, eliminating it entirely or lessening its severity.
The inactivated polio vaccine (IPV) is known to prevent conversion of polio infection from a gut infection to a neurological disease. It doesn't prevent infection by polio in the gut.
The herpes zoster vaccine also doesn't prevent infection, as I understand it, but generally this vaccine is used in people who are already infected in order to prevent symptomatic disease (shingles) in the case of virus reactivation.
If we go into the realm of bacteria, there are additional vaccines in widespread clinical use that prevent disease without preventing infection, but I'd rather stay in my lane of viruses since I've described enough examples already, all of them in widespread clinical use.
Another problem with this answer is that it doesn't actually matter whether the vaccine prevents infection or not, at least not for the purposes of answering this question. It seems like Dr. Sax is conflating infectivity with transmissibility, which isn't correct. Just because a virus can infect a host does not mean that that host can then spread the virus again. The issue being addressed by the question is whether the vaccinated host can spread the virus again, not whether they can be infected with it. It's true, though, that a vaccine which causes sterilizing immunity (prevention of infection entirely) will also prevent transmission, because the virus never infects and never replicates. What is less clear is whether, in the absence of sterilizing immunity, the virus can still be transmitted from the host.
The best example of this situation is with the IPV, where immunity is not sterilizing and people who have received the vaccine can very much play host to, and continue to transmit, the polio virus. It's a real thing and I'm surprised an infectious disease doc like Dr. Sax is unaware of it. Perhaps he is not aware of it because he largely practices in the US, where polio has been eradicated. This eradication is actually part of the reason that the US switched from administering oral polio vaccine to now using IPV; since the virus is no longer actively transmitting in the US, IPV is considered a safer option. The oral polio vaccine has a chance of reverting and causing polio in some patients.
We really just don't know the answer to this in the context of SARS-CoV-2. I believe it is likely that there is an effect on transmission in the context of these vaccines, but without data I am giving you a hypothesis, and I've had a lot of hypotheses in the past that have not borne out in the data.
Let's explore the hypothesis, though. First, we have to imagine two possible conditions. (1) The vaccine provides sterilizing immunity; in this situation, there is never an infection and so disease and transmission are bother prevented (2) The vaccine prevents the virus from causing disease by controlling the infection; sterilizing immunity is not achieved
(2) is a situation that could be caused by a number of different effects. It could be that disease is mostly mediated by an immune overreaction and when immune memory is present, that effect is reduced but the virus still replicates adequately to spread. We know that this situation is possible because we have evidence of people who are asymptomatic being able to transmit SARS-CoV-2 to others. So it's not beyond the realm of possibility that we have created more asymptomatic carriers with this vaccine. On the other hand, control of the disease may be achieved through an immune response that reduces the overall replication of the virus, and thus prevents transmission as well. This also seems fairly plausible.
As I've said in the past, I think it's also possible that the vaccine causes some kind of intermediate state--disease is no longer possible, and the capacity for transmission is reduced but not totally eliminated. I mention this possibility because it's important to realize that very few biological processes are binary. There is usually a continuum of possible states that exist between two potential extremes. This is one reason we need data on the ability of the vaccines to prevent transmission.
Back to the subject at hand: Due respect to Dr. Sax, I think he just gave a bad answer here. We all do that sometimes. He was asked about transmission and he answered about infection. Worse, he answered incorrectly about infection. I think that NEJM should retract the post. it's causing confusion and it doesn't contain accurate information.
Also, Carl Fink had a suggestion for future content:
Hey, John, have you written about antivirals? A diet of all vaccine essays is probably getting dull, and I find it disappointing that we still have no effective antiviral medications against SARS-CoV-2. (No, I don't think that remdesivir is actually doing anything.)
It’s a good suggestion. I’ll try and write some about the current state of antivirals soon. I still owe you all an interview (it’s being worked on!) about viral vector/chimeric vaccines, which also came at Carl’s inspiration. Look for that this week.
You might have some questions or comments! Send them in. As several folks have figured out, you can also email me if you have a comment that you don’t want to share with the whole group.
Join the conversation, and what you say will impact what I talk about in the next issue.
Also, let me know any other thoughts you might have about the newsletter. I’d like to make sure you’re getting what you want out of this.
Part of science is identifying and correcting errors. If you find a mistake, please tell me about it.
Though I can’t correct the emailed version after it has been sent, I do update the online post of the newsletter every time a mistake is brought to my attention.
Correction: Yes, there was a typo in the subject line of yesterday’s email. “Fro” should have been “for.” Unfortunately this cannot be fixed after the post goes out, even in the online edition.
See you all next time.
Always,
JS