Why you should trust the coronavirus vaccine

Let me start by making one thing clear: at the time of this writing, we don't have a scientifically validated vaccine for COVID-19. But more than 150 vaccines are being developed around the world, and many of them are already in advanced stages of testing.

So we'll have a vaccine soon, likely in a matter of months. And everyone should take it. I know I will.

Today I’m going to try to de-mystify vaccines a bit, in the hope that this might help people feel more comfortable with them.

Before explaining what a vaccine actually is, let me point out that vaccines are probably the single greatest medical advance in the history of human civilization. Vaccines have saved hundreds of millions of lives: prior to vaccines, people lived in fear of diseases like smallpox, which killed 300 million people in the 20th century alone. Thanks to the vaccine, we eradicated smallpox from the entire world in 1980. Polio is another dreaded disease that killed or permanently injured millions, until the 1950s, when Hilary Koprowski, Jonas Salk, and Alfred Sabin invented vaccines that protected against it. Today, no one in the U.S. or Europe worries about polio, and it too has nearly been eradicated worldwide.

What exactly is a vaccine? It’s a pretty simple concept. Our immune system has the remarkable ability to “remember” pathogens that we’ve been exposed to. So once you’ve been infected with some viruses or bacteria, you acquire immunity to those diseases that may last the rest of your life. A vaccine is basically a way to teach the immune system to recognize a pathogen without actually making you sick.

The simplest way to do this (conceptually) is to take a batch of viruses or bacteria, kill them so they’re harmless, and then just inject them into a person. The immune system then “sees” the proteins in the dead pathogens (because the proteins are still floating around), and it learns all it needs to know from these. Later on, if a live virus infects that person, her immune system will say “aha, I know you!” and will quickly surround and destroy the invaders.

Simple as it sounds, there are many complications with this process. One is that it’s often very hard to isolate and grow enough of the virus (or bacteria) for large-scale production. The viruses then need to be isolated, killed, and purified, which can be complicated and costly. For COVID-19, though, any cost is worth it.

Another, much newer way to make vaccines uses modern molecular technology to make RNA. There’s no need to isolate or grow the virus at all! This is how Moderna’s new mRNA vaccine works (see their whitepaper here).

The mRNA vaccine relies on the fact that we already know which protein in the SARS-CoV-2 virus is the most important one. It’s called the spike protein, so I’ll just call it Spike. Spike is what attaches to human cells and lets the virus infect them. We also know the sequence of the Spike gene: the sequence of the entire SARS-CoV-2 virus was released in early January, and we’ve now sequenced thousands of these viruses.

An mRNA vaccine simply uses the RNA itself, rather than dead viruses. Today we can synthesize RNA in large quantities, so if you take some of this RNA and inject it into a person, what happens? Well, our own cells will translate this RNA to produce the Spike protein. All by itself, the protein cannot possibly cause an infection. It’s analogous to having a motor without a car: you can’t go anywhere without the whole package.

But here’s the good part: our immune system will recognize Spike anyway, even without the virus, and it will remember this invader. So the RNA vaccine is, in theory at least, even safer than traditional vaccines, because live pathogens are never used in the production process. (Before the anti-vaxxers jump on me here, let me emphasize that traditional vaccines are incredibly safe.)

This is just one example: there are 23 vaccines already in human trials, and over 150 in development, using mRNA, proteins, and other approaches.

There are other ingredients in vaccines too: preservatives and adjuvants. Anti-vaxxers like to read vaccine ingredients and then claim that all sorts of harmful stuff is in there, but their claims are mostly just gross ignorance. Preservatives are there to prevent the growth of things like bacteria, so they make vaccines safer. And adjuvants like aluminum salts (the most common adjuvant) are ingredients that enhance the effectiveness of vaccines, meaning you can use a lower dose. Aluminum salts have a very long safety record.

So why don’t people trust vaccines? Largely because the anti-vaccine movement has spent years spreading misinformation and fear, and it is already pronouncing strong opposition to any coronavirus vaccine, regardless of the evidence. The New York Times reported this week that mistrust of future coronavirus vaccines could imperil public health, especially in the United States. Polls have shown that large proportions of Americans say they won't take a vaccine even when it's available, which is, frankly, kind of crazy. (It didn’t help when tennis player Novak Djokovic expressed doubts about whether he’d be willing to take any future coronavirus vaccine.) Last month, NIH’s Anthony Fauci said that the “general anti-science, anti-authority, anti-vaccine feeling” in the U.S. may seriously undermine the effectiveness of any future vaccine. Of course, this could change once we really do have a vaccine, and we should all hope it does. But the anti-vaxxers never let up.

It also doesn't help build trust when the Trump administration calls their vaccine program "Operation Warp Speed." This might have sounded exciting to some sci-fi fans in the White House, but to many people it sounds more like a devil-may-care approach that emphasizes speed over safety. 

So how do we establish trust in the new vaccines, which are probably coming just a few months from now? One way to reassure people is to publish all the numbers from the vaccine trials. A just-published study in NEJM on the Moderna vaccine (the RNA vaccine) provides exactly these numbers, and they look very good in terms of both safety and effectiveness. 

In that study, all 45 participants had a robust antibody response–a stronger response, in fact, than in many people who’d been infected with the virus itself. There were some side effects, including fever and chills, but all were graded as mild or moderate. The scientists looked at 3 different dosage levels, and the side effects were greatest in the highest dose–but the antibody response was perfectly adequate in the lower dosage levels. So the next phase of testing, already under way, is using the lower dosages.

This was a phase 1 study, but it's very encouraging. If these results hold up in a large group–a question that is being tested now, in a phase 3 study–we'll have a working vaccine. 

And if you want to know more about this trial, you can read about it at the public NIH site, ClinicalTrials.gov.

Many if not all of the vaccines being developed in Europe and the U.S. are going through the same kind of scrutiny, and we’ll be able to see the results of those tests too. This is how we generate trust in the results: share them openly. I’m very re-assured by what I’ve seen so far.

The bottom line: vaccines work, and our methods for testing them are rigorous and thorough. With a little luck, the world will have multiple COVID-19 vaccines by the end of 2020. Once we have enough people vaccinated, our long nightmare with the coronavirus pandemic will come to an end.

Are you "vaccine hesitant"? You may be in a cult

Edward Jenner, who pioneered vaccination, and two colleagues
 (right) seeing off three anti-vaccination opponents, with the dead
lying at their feet (1808). I Cruikshank/Wellcome Images/Wikimedia
Commons, CC BY-SA

The World Health Organization recently declared that "vaccine hesitancy," as they called it, was one of the top 10 threats to global health. That's right: it was up there with air pollution, climate change, influenza, Ebola, and other threats.

For the WHO, "vaccine hesitancy" is a polite phrase designed to engage the public and highlight how serious the problem is, without angering those who are guilty of it. I'm not going to be quite so polite here: "vaccine hesitant" means anti-vax. The anti-vax movement, which aggressively spreads fear and misinformation about vaccines, has become a major, worldwide threat.

It also resembles a cult, as I'll explain.

The most recent anti-vax nonsense centers on the new coronavirus that originated in China, and that has led the Chinese government to impose a massive quarantine affecting millions of people. This is a genuine public health crisis, and it has nothing to do with vaccines. Nonetheless, some anti-vaxxers are claiming, without evidence, that the new virus originated from a failed effort to create a coronavirus vaccine. I don't have time to get into that here, but Orac has a lengthy, detailed takedown of that bogus claim.

"Vaccine hesitancy" sometimes refers to parents who are just learning about vaccines for the first time, and who rely on the Internet to search for information. Unfortunately, these new parents are likely to be flooded with anti-vax messages, especially on Facebook. (In recent years, Google has taken steps to lower the priority of anti-vax sites, which has improved things considerably. Sites such as healthychildren.org now appear near the top of searches for "vaccine safety.") It's entirely reasonable to ask your doctor about the benefits and risks of vaccines.

But the answers that parents hear should be clear: vaccines work. As physician ZDoggMD (a pseudonym, obviously) explains in this video:

"Anti-vaccine sentiment is a poisonous scourge.... There's no debate about vaccines. Let's get over that nonsense that the media and celebrities have created, okay? There is nobody in the medical community of any actual reputation who believes that there are two sides to this."

The problem is that anti-vaxxers are continuously creating new websites, Facebook groups, and even movies to spread misinformation about vaccines, particularly the long-debunked claim that vaccines cause autism.

Why do I suggest that anti-vaxxers resemble a cult? Because they have several of the key features of cults, such as:

1. Members of the cult have special insights that outsiders cannot comprehend. With anti-vaxxers, this means they are completely convinced that they know that vaccines cause harm, despite mountains of evidence to the contrary.
2. The group and its leaders are the exclusive means of knowing "truth" or receiving validation, and no other process of discovery is credible. The anti-vax movement has had several prominent leaders, whose followers flock to their speeches and events. These include Andrew Wakefield, the disgraced former doctor who lost his medical license after it was revealed that he had committed fraud. His followers, though, either don't know or ignore his fraudulent past, and regard him as a hero. He makes a living from his books, a movie, and speaking fees, all based on spreading fear about vaccines. An even more prominent anti-vax leader is Robert Kennedy, Jr., who also sells books and gives speeches proclaiming the harms of vaccines. Thanks to his famous name, and despite the fact that he has no medical or scientific training, some people believe him.
3. Unreasonable fear about the outside world, such as impending catastrophe, evil conspiracies and persecutions. Conspiracy theories are the core of many anti-vax arguments. The most common version holds that the "medical establishment" (whoever that is) are hiding the dangers of vaccines so that they can make money. This is utter nonsense. All of doctors I know in the infectious disease community are motivated by a wish to cure disease. In any case, most doctors make little or no money from the vaccines they administer.
4. No meaningful financial disclosure regarding budget or expenses. Some anti-vaxxers profit handsomely by selling bogus, ineffective supplements as alternatives to vaccines. (I'm looking at you, Joe Mercola.) Because supplements are largely unregulated, they get away with it. They'd prefer you to think they're "just in it for the children."

I've no doubt that anti-vaxxers like Wakefield, Kennedy, and others would deny that they are conspiracy theorists, because that's how conspiracy theorists operate. If you question them (they argue), you must be part of the conspiracy. By their own reasoning, they can never be wrong.

So if you encounter someone, either on the sidelines at your kid's soccer game, on Facebook, or elsewhere, who is spreading claims that vaccines are harmful, pause for a minute and ask: what is the source of this information? Is it coming from someone who is profiting from this fear-mongering? There's a good chance the answer is yes.

It's ironic that when the world is faced with a true health emergency, such as the Ebola virus or the Wuhan coronavirus, the first thing that public health experts start to work on is a new vaccine. That's because vaccines provide our best protection against infections. We now have effective vaccines for 16 diseases that used to harm and even kill children in large numbers around the world. We've eliminated smallpox worldwide, and we've nearly eliminated polio, thanks to vaccines. Their very effectiveness is what has allowed the anti-vax message to take hold: many people are no longer frightened of dying from infectious diseases.

We're still a long way from conquering infections, but there's no reason for the world to slip back in time to an era when large numbers of people died from preventable infections. Vaccines work, if we'll let them.