COVID-19 misconceptions and more
Moderna's vaccine is approved, how COVID-19 vaccines actually work, whether we should worry about reactions to vaccines, rhinos in Tibet, marsquakes, and more
Hello, friend! As we get started, I want to share two numbers—
0.
200,000+.
Those are the numbers of scientific papers, preprints, and reviews that deal with COVID-19 that were available on January 1 and December 15, respectively. At the start of the year, there were none. Now, we have over 200,000 contributions. We shouldn’t lose sight of what a year it has been and how tirelessly so many people around the world have worked to help us defeat this scourge.
Thank you!
I am truly grateful to all the scientists and healthcare workers this year who made astounding discoveries at breakneck speed. We have drugs and vaccines. We know so much about the virus and how it spreads.
Soumitra Chatterjee (who died this year) playing a misunderstood infectious diseases specialist in Satyajit Ray’s Ganashatru (based on Henrik Ibsen’s An Enemy of the People).
I am also grateful to the essential workers who made sure society functioned. I am grateful to the shopkeepers, factory workers, and deliverymen. I owe a debt of gratitude to the farmers, first-responders, garbage-collectors, and custodians. I am grateful to the teachers and professors because there is no life without learning. I am grateful to the artists and writers and musicians, because human life is not just staying alive and breathing.
In a very small way I have tried to document what we have learned about the virus and how we lived through this year in COVID-19: Separating Fact From Fiction, which is slated for publication in early February. I have used conversations through this year with scientists (often on much-maligned Zoom and through webinars) to learn more. I have read more about one topic than I ever have since completing my PhD.
I am also very grateful to you. You didn’t know it, but when you asked me questions on Twitter, or shared a particular newsletter, or liked a tweet you helped me to develop the book. I used polls I created, threads, and conversations to figure out what you wanted to know. So, I’d like to acknowledge your feedback. It has been very helpful, and once the book is out, I hope you find it helpful too.
Another vaccine is approved for emergency use!
Moving right along… We have another vaccine! Moderna’s vaccine breezed through the FDA advisory panel’s discussion on Thursday. This vaccine has a less stringent cold chain than Pfizer’s mRNA vaccine. Both vaccines were designed to protect against clinically identified COVID-19, and are roughly the same in terms of efficacy. Moderna’s vaccine also had >60% efficacy in preventing infections after one dose. Moderna will be testing transmissions as well at a future date. All of this is good news.
Which vaccine would I take if given the option to choose?
Right now, I would take either Pfizer’s or Moderna’s, whichever was offered to me first.
Should we worry about allergic reactions or Bell’s palsy?
It’s important to remember that when we immunize a very large number of people, there will always be a background of adverse events. Just because someone had an adverse event after getting vaccinated doesn’t mean that it happened because they were vaccinated. Right now after public discussions, the FDA is confident that these vaccines are safe: there are no major concerns with the reported cases of allergic reactions or Bell’s palsy. The FDA will continue to monitor for the occurrence of other events.
Should you get vaccinated if you’ve already been infected once?
Yes. Even if there is reason to suspect that you have post-infection immunity, you should get vaccinated when your turn comes. Reinfections after natural infection have been observed. Besides, we don’t know the correlates of immunity yet. In other words, even if you have been infected, you don’t know the actual “strength” of your post-infection immunity and how long it will last. Why not get vaccinated when you get the chance?
I’ve discussed all of these topics, and what we can expect in 2021 in a podcast episode with Shrikant Joshi which you can listen to here.
Seven misconceptions with respect to COVID-19
There are several misconceptions with respect to COVID-19 and vaccines that are floating around that I’d like to dispel. I’ve picked seven points that I’d like to elaborate on briefly. All of these will be covered in more detail in the book.
Infection is not the same as disease. This one should be reasonably obvious more than nine months into the pandemic. Everyone who is infected with the SARS-CoV-2 virus will not have clinically symptomatic COVID-19. This is one of the hallmarks of SARS-CoV-2 that makes it difficult to control compared to other viruses like SARS.
Infected is not the same as infectious. Anyone who has detectable SARS-CoV-2 virus inside them can be said to be infected. But that doesn’t mean that they’re infectious, for that they need to be shedding viable viruses that can infect others. People are typically infected for much longer than they are infectious.
RNA is not the same as infectious virus. The presence of viral RNA which is a telltale sign of the virus, doesn’t mean that there’s intact virus inside that can infect other people. Viral RNA can be detected as debris post infection for many days. This is one of the aspects of the molecular diagnostic RT-PCR test that many are not fully aware of. A positive result weeks after infection doesn’t mean that the person is necessarily infectious.
Efficacy is not the same as effectiveness. Efficacy in a clinical trial indicates whether a vaccine or drug works under the parameters of the trial. It’s a good indication of whether or not it will be effective in the real world, but they’re not the same thing. Once you start to roll out drugs in the real world and monitor for months and years in heterogenous populations, you can determine effectiveness.
Herd immunity does not imply zero transmission. Reaching the herd immunity threshold of around 70% for SARS-CoV-2 doesn’t mean that transmissions of the virus stop. People will continue to get infected, but the parameters of the epidemic will change because there are now fewer susceptible people to get infected. We have to keep in mind that millions of babies are born every year who are immunologically naïve.
Immunity for SARS-CoV-2 probably won’t confer life-long protection from infection or disease. Over time, immunity either as a result of infection or vaccination might wane. This can happen naturally as antibodies and T cells decline. It can happen in elderly people more rapidly as well, by a process known as immunosenescence. On the other hand, the virus might also mutate over time to evade acquired immunity. So far, the fears of mutated viruses escaping immunity conferred by COVID-19 vaccines are unfounded.
The end of pandemic does not mean the virus will be eradicated. I’ve talked about why SARS-CoV-2 is never going to be eradicated here. The pandemic will end after there are fewer people available to infect. But what happens after that? Preeminent epidemiologist Dr. Marc Lipsitch offered his take to the New York Times—
“Viral infections this widespread don’t disappear on their own that I’m aware of, unless they’re out-competed by some new strain.”
He suggested, however, that Covid-19 might become less severe in the long term. “If everybody essentially in the world who’s not a newborn has either had the virus or had the vaccine,” he said, “there would be some immunity to severity, and some immunity to transmission, and so if I had to make a guess I would say it would become a seasonal disease like the flu.”
How COVID-19 vaccines work
Do you ever wonder how COVID-19 vaccines in general, and mRNA vaccines (like Pfizer’s and Moderna’s) in particular work? Here is an amazing two-minute video that explains all the basic concepts.
What else I’m reading:
Tropical Tibet!
Researchers have found that that the Indian gaur and the Sumatran rhinoceros were hunted in the lush Tibetan Plateau only 5,200 years ago. Obviously, Tibet and northern China no longer looks like this. In the not-to-distant past, rhinos were found all across China.
If Earth has earthquakes, then Mars has…
Marsquakes. That’s the correct answer. Also, the crust of the red planet is layered like a cake. NASA’s InSight yields the first data on the structure of a planet (other than Earth, of course).
Water of life.
Water is necessary for the origin and sustenance of life. But water also breaks down molecules necessary for life. How can we reconcile this situation? Here is a wonderful feature in Nature this week with the answer.
When pigs fly (well, almost)
The first genetically-modified pig got approved in the US. This alteration removes a sugar on the surface of some of the cells of pigs. This clears the way for the use of these GM pigs for food and also for biomedical products.
Pluto revisited.
Five years ago New Horizons flew by Pluto and gave us some of the most iconic images of the decade including Pluto's "heart". Here are ten cool things we've learned about Pluto from that piano-sized probe.
Image: NASA
Feeling Awe is Good for You.
Being wonderstruck by the natural world has benefits.
When do people feel as if they are rich in time? Not often, research and daily experience suggest. [People] who felt awe, relative to other emotions, felt they had more time available and were less impatient.
2020 also gave us…
This Nazca Line geoglyph of a cat created around 2100 years ago.
(Photo by the Peruvian Ministry of Culture)
Final thoughts…
In the modern era, we have neglected viruses. And experts have been sounding the alarm for decades. One of them was microbiologist and Nobel Laureate, Joshua Lederberg. In 1988, at the height of the AIDS epidemic, he wrote the following prescient paragraph in an article in Social Research—
Update: The link for the hardcover “COVID-19: Separating Fact from Fiction” is now available on Amazon’s Indian site. Here’s the link to the Kindle version on Amazon.com.
Here’s an excerpt of the book in which I talk about how so many COVID-19 vaccines were developed so quickly (and why they’re not the same).
If you enjoy the book, please do leave me a review on Amazon or on Goodreads.
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Very simply explained, though I am yet to go through links you have provided except vaccine video. So for layman like me this makes things very clear. I always believed I could not understand anything even remotely related to science, your blog and tweets have made it easier to understand.