There is a terrific video bit done by Penn and Teller explaining the benefits of vaccines versus the non-existent risk of autism. They throw grapefruits at miniature bowling pins arranged on the floor. Penn’s side has a big plexiglass screen representing vaccines. The grapefruits bounce off. On Teller’s side, the helpless unprotected children are decimated with every throw. And while I totally agree with the message, immunity is not a force field. That is not how it works.
This came to mind for me recently after reading yet another let’s-open-the-economy-it-will-all-be-over-soon pollyannaish article in the Wall Street Journal entitled authoritatively “We’ll Have Herd Immunity by April”. It was written by Dr. Marty Makary who practises surgical oncology and advanced laparoscopic surgery at Johns Hopkins (not infectious disease, virology or epidemiology, for example).
The analogy is wrong
Makary should not be faulted for the graphic that accompanies the WSJ article. That was created by Martin Kozlowski, and is reproduced here:
You will note that vaccination is again being represented by a lexan/plexi extra-corporeal shield. We are now all well-tuned to the idea that what protects us are face masks, and maybe (but probably not) face shields. That’s because, even though there was no convincing evidence of masks protecting you from others prior to March of 2020, there was then and is now convincing evidence that masking-up protects others from you. And it does that far better than masking protects you from others. My friend Matt Pottinger was the first person to wear a mask in the White House, not because he was trying to protect himself so much as he did not want to go down in history as accidentally killing the President and half of his cabinet at the dawn of a pandemic.
Wearing a face mask is an act of civic duty. So is getting vaccinated.
But, the immunity you get from a vaccine is not a force field that stands 3 feet outside of your body. Immunity will do absolutely nothing to prevent you from being infected any more than a seatbelt prevents you from being in a car accident. Boiling water on a stove does not kill Salmonella until you put the egg in the boiling water. A seatbelt’s protection happens when you are in a car accident. And the immunity you get from a vaccine only matters if you get infected.
What vaccines do
… what the immunity from vaccines does… is first and foremost keep you from dying. With any luck, that also means you will also not get sick, because if you don’t get sick you’re not going to die. That is the point after all.
Now, there’s a very nice side effect to this. If it is a respiratory virus, like a coronavirus or measles virus, and you are not sick, you are less likely to be coughing and sneezing; not not-at-all, but hopefully not-a-lot.
It should be no surprise to anyone with a basic understanding of evolutionary biology that a respiratory virus that makes you cough and sneeze is one that is going to be much more successful at being a respiratory virus than one that does not do that. As such, if your immunity prevents you from coughing and sneezing when you are infected, then you are less likely to infect other people and you are getting in the way of the virus’ evolutionary success. So being vaccinated protects you and protects other people from you. It even protects your evolutionary descendants from you, which after all was the point of this:
“By the toll of a billion deaths man has bought his birthright of the earth,
H. G. Wells. The War of the Worlds.
and it is his against all comers; it would still be his were the Martians
ten times as mighty as they are. For neither do men live nor die in vain.”
Before there were vaccines, all of this was an epic many-million-year pitched battle for victory: either some of us would survive or all of us would perish. Without the mRNA vaccines and other efforts by sentient thoughtful scientists, COVID-19 could have easily reduced human life expectancy by about 20 years, thus wiping out a century of medical progress. Good thing that viruses are not sentient.
Vaccines prevent disease, not infection
Vaccines are the best inventions ever. Seriously. But when you understand how immunity works, you’ll see what I mean about them not being force fields.
I got measles in 7th or 8th grade. I got “German” measles (i.e., Rubella) too. I even got mumps. All of this notwithstanding that I had the MMR (i.e., measles, mumps, rubella) vaccine. Seems that a batch some of us got in Southern Ontario in the late 60s or early 70s did not confer long-enough lasting immunity. I wasn’t the only one. That’s not an argument against vaccines. It’s a reminder of Murphy’s Law.
That being said, because I got measles the old-fashioned way, through my nose and mouth and lungs, I have what is called “mucosal” immunity as well as having “humoral” immunity. It’s actually quite simple. In your nose and mouth (and other orifices) the antibodies produced are of type “A” (literally IgA). The antibodies in your blood are of type “G”, or IgG. I have both. If you got vaccinated by an injection, you will soon mostly have IgG (and IgG B-cells that “remember”) in your blood, not IgA in your nose and throat. This is also why the oral vaccine for polio and for typhoid are better than the injected ones (even though that concerns an aboral orifice.
This matters not a whit as to whether you will get sick or die of measles; if vaccinated you’ll be fine. But it matters enormously to the circulation of the measles virus around you, and after you. We are getting reinfected with measles all the time… all the time. We’re just not getting sick. It ran rampant through a part of Brooklyn recently and through anti-vaxxing California before that.
It’s not like measles is being spontaneously generated at night like mobs in Minecraft. Measles is all around us all of the time. (This is, after all, the premise of how we defeated the Martians in The War of the Worlds). And it’s in us… only us… not in our dogs and cats. There is no other species that gets measles. Anywhere. Everyone who gets measles gets it from another human being who is infected.
But not from me.
The likelihood that I will pass on measles (having had it) is 10 times less than the likelihood that you will (if you were vaccinated but never had it). I have a 2% chance of passing this hot-potato with an R0 of 18. That comes to my being unlikely to pass it to even one person. You have a 20% chance! Yes, that’s right. With an R0 of 18 and a 20% chance, you are likely to infect 3 people you encounter after you get infected with measles even if you just get a runny nose or a couple of sneezing spells.
This is why everyone needs to get vaccinated. It is your civic duty. Most of can still pass measles around even if we’re all vaccinated. And there are people out there who are immunocompromised, or elderly, or who have had organ transplants who are basically immunologically naked. Everyone needs to get vaccinated to protect those people. People you don’t even know.
Whatever happened to civic duty? Who created the message that vaccination was about self-protection when it’s really about selflessness and caring? Is this uniquely American?
COVID
The mRNA vaccines for SARS CoV 2 are awesome. The achievements in terms of science, never mind even having them under a year, will fill the pages of immunology and epidemiology texts for centuries hence. But they are injected, not suffused through the nose or mouth. And as such, they are not likely to induce mucosal IgA immunity. That means that, like measles, we cannot be complacent about the vaccinated being able to carry and transmit to others.
This pandemic and its hallmark super-spreader events has already been driven by asymptomatic sources spreading to others before those sources fall ill. The duration of this crisis will only be made longer by people believing that once-vaccinated they no longer bear responsibility for their ability to infect of others.
Vaccinated or not, wear a mask. Celebratory parties for vaccinated-only people, and precipitous openings by workers with “vaccine passports”.. these will prove to be super-spreader events.
“A crisis is made by men, who enter into the crisis with their
own prejudices, propensities, and predispositions. A crisis is
the sum of intuition and blind spots, a blend of facts noted
and facts ignored.”
― Michael Crichton, The Andromeda Strain
I caught that Minecraft reference.