CommentsGELFAND’S WORLD--By this I mean something that goes on and on, sometimes becoming horribly painful and always, even for the noncombatants, an enduring irritation – months that creep into years and, in a worst case scenario, half a decade. And every night on the TV news, we are told the latest death toll.
There are a couple of issues with this scenario, mainly dealing with (1) the prospects for an effective vaccine and (2) at a more speculative level, the chance that many of us will turn out to have some little bit of innate immunity – enough to prevent a small infection from going to full blown pneumonia. More about this later.
There is one point that deserves to be made at the outset. A huge amount has been learned about biology over the last half century, so much that the basic questions about this disease were mostly answered within the first couple of months of its origin. The origin of the virus was determined from among the first patients (people who actually worked at or around the seafood market where it first appeared) and was immediately shown to be related, but not identical to the virus that caused the earlier SARS outbreak. The researchers determined and published the sequence of the viral genome. They analyzed the neo-corona virus proteins, showing which proteins there are, and how they differ from earlier versions of the virus.
One notable fact that is worthy of mention: For a long time now, researchers who determine the sequence of a gene are asked to send that sequence to one of several archives which collect DNA and RNA sequences and make them available to other researchers. For this reason, the scientists who analyzed the new virus were able to understand its structure, the proteins it makes, and therefore a lot about how the virus gets into cells, replicates, and moves on to other cells. Within days, scientists all around the world knew these results.
The new corona virus was just one more among a collection of already known (and archived) viruses. Think of it like this: If you were an auto mechanic confronted with the latest Chevrolet, you would understand a lot about it even though you had never seen that exact model. You would understand that there is an engine, that there is a transmission, and those are the wheels. It was somewhat the same way with the new virus.
Here is the problem, and possibly maybe a solution
It turns out that it isn’t all that easy to make a vaccine that does everything we want it to do. We want it to inspire your immune system to make antibodies against the virus. When you read about the body’s adaptive immune system, that is what they are talking about. But there is another, really critical factor. You don’t want the vaccine to cause the body to do harm to itself. For example, it is known that this virus gets into cells by attaching itself to a protein called the angiotensin converting enzyme (ACE), and you don’t want the vaccine to create an autoimmune reaction either against ACE or some other critical part of the body.
Here's an example of an autoimmune reaction (that is not caused by a virus or a vaccine, but by a bacterium): Once in a while, somebody will get strep throat and let it go too long. In some such patients (about 3%), their own immune system makes antibodies that react against the cells on their own heart valves, leading to substantial damage. The condition used to be known as rheumatic heart disease. Nowadays, doctors check for strep infections and cover the condition with an antibiotic.
It turns out that creating a vaccine that is effective and safe is not necessarily easy, and has usually taken quite a long time. There have been lots of failed attempts at making new vaccines. If you want to learn more about vaccine discovery, you can read Paul Offit’s book Vaccinated.
In the case of Covid-19, there is a bit of an advantage. There are at least 40 labs and companies now working on a vaccine. Some of them are trying novel methods that haven’t been successful so far, but have shown some promise. Others presumably are pulling out the old, tried and true methods such as growing up the virus, inactivating it with something like concentrated formaldehyde, purifying the remnants, and testing the product in some animal.
Of course to do this kind of research, you need to find an animal where the virus grows, and it ought to be an animal that has an immune system something like our own.
The blogger who goes by the pseudonym Skeptical Raptor has written a series of articles about the difficulties of creating the Covid-19 vaccine. You can find a list of all the companies currently working on a vaccine here. You can find a discussion here suggesting that it could take 3-5 years or more to develop a safe and effective vaccine. James D. Walsh in New York Magazine has an essay on the difficulties of vaccine development that you can find here.
Finally, David Wallace-Wells suggests the possibility that we are only about one-tenth of the way through this epidemic, which you can read here.
What these authors point out is that vaccine development isn’t necessarily predictable. It is full of possible pitfalls, and sometimes the developers have to backtrack a bit in order to adjust dosages or redesign steps in production.
The traditional pathway to vaccine design involves more like 7 to 10 years.
The good news, if you can call it that, is that the whole world is in tune with finding a cure or prevention, which means that there are a lot of hands and minds trying things even as we speak. Instead of trying 40 different approaches one after the other, the world is now trying 40 different approaches simultaneously.
Even then, even if the sought after miracle occurs, we might be looking at a period of a year before the safety and effectiveness of a new vaccine is demonstrated. At that point, there will be a rush to manufacture enough of the vaccine to immunize billions of people. That’s where the incredibly optimistic hope for a vaccine in 12-18 months comes from. It’s optimistic assumption piled upon optimistic assumption.
Here’s a cautionary point from the authors of the articles linked above: Don’t take seriously any promises made by the biotech and pharmaceutical industry people – they are speaking to their investors and overpromising what they can do. Clinical testing is what is required, and that is what is going to take a while.
A super-optimistic scenario
In the opening paragraphs, I wondered whether some of us are already a little bit immune. That might explain why the entire population of Los Angeles County (or every person in New York City) has not yet come down with the disease. There could potentially be some aspect of innate immunity that science does not as yet understand.
You see these thoughts percolating (yet largely unspoken and unwritten) in a lot of the analytic arguments going on among the pundits right now. Some are wondering whether there have been ten or fifty times as many cases as have been confirmed by testing, an assumption that would imply that there are lots of people who get asymptomatic infections and fight them off without even realizing what is happening. If that is the case, then opening up commerce and travel might be OK for those who are unknowingly immune. It’s an experiment that most politicians wouldn’t want to try.
But as the epidemic goes on and people get more stir crazy, we are going to see a huge, uncontrolled, real-life experiment as more and more people simply start breaking the rules.
Or we might see the secular version of a true miracle, and get either an effective treatment for the early stages of the illness, or a working vaccine before the end of the year.
(Bob Gelfand writes on science, culture, and politics for CityWatch. He can be reached at [email protected])
