Why the new COVID vaccine boosters are safe and likely very effective

In case you haven’t heard, there’s now a new set of vaccine booster shots that protect against the latest variant of Covid-19, BA.5. This new variant is highly infectious, and the original vaccine doesn’t protect people against it as well as it protected against earlier variants.

Now, before someone takes that last sentence out of context, let me emphasize that the original Covid-19 vaccines are still highly effective at preventing severe disease and hospitalization. Anyone who isn’t vaccinated would be well-advised to get one of those, if that’s their only option.

But the new vaccines protect against two different strains of Covid-19: the original strand and the latest Omicron variant, BA.5. BA.5 just emerged in August, and it’s spreading extremely fast–it now accounts for 88% of the cases in the U.S. The FDA authorized these “bivalent” boosters on August 31.

My main point today is to explain how this happened so quickly, and why it didn’t involve many months of clinical trials the way that the original vaccines did. Some people have expressed suspicion about the speed with which these boosters appeared, but those suspicions are entirely unfounded.

First of all, we do have data showing that the new vaccine boosters are safe: a study showing these data for the Moderna booster just appeared in the New England Journal of Medicine. That study also showed that people generated robust antibodies against the BA.1, BA.4, and BA.5 Omicron variants after getting the new booster.

Second, to explain why that’s all the data we need, let me explain something about the flu vaccine. Many people are well aware that we have a new influenza vaccine every year–but what they might not know is that each year’s vaccine contains a different strain of the flu virus from the previous year. (Actually, it has up to four different strains, and any or all of them could be new.)

And yet we don’t run large, months-long clinical trials of the flu vaccine each year to measure it’s efficacy. Why not? Well, the basic designs of the flu vaccines (there’s more than one) have been tested in large clinical trials, and we know they’re safe. Replacing the vaccine strain with a new one doesn’t affect the safety of the vaccine, as decades of experience with the flu vaccine have now demonstrated. And because flu mutates quickly, we need to change the vaccine strain every year if we want the vaccine to work.

So that’s what we do: we change the flu vaccine strain to match whatever seems to be circulating, but everything else about the vaccine design remains the same.

This is exactly what scientists have done with the new Covid-19 booster shots from Pfizer/BioNTech and Moderna: they simply added a new strain, in this case to match the latest Omicron variant.

Both of the new boosters are mRNA vaccines, which means the vaccine contains a tiny bit of genetic code (mRNA) with instructions on how to make the “spike” protein from SARS-CoV-2, the Covid-19 virus. When you get the vaccine, your own cells follow those instructions to make a limited number of copies of the spike protein–but nothing else. The virus itself can’t be created without many other genes, and the spike protein alone can’t form a virus.

But your immune system recognizes that an invader is present–that spike protein–and it generates antibodies against it. After that, your immune system is primed to recognize and defeat Covid-19, if it ever infects you.

So the new boosters contain mRNA from the BA.5 spike protein as well as the original spike protein, and now you get protection from both old and new strains. Other than that, it’s the same vaccine as before.

The vaccine makers have produced safety data showing that the booster is just as safe as the original vaccine (see that NEJM article I mentioned above). But the FDA didn’t require them to prove that the booster really works better against BA.5, because that would require months of trials, and by that time the virus could mutate again. So while it’s possible that the boosters won’t help against BA.5, it’s very, very likely that they will.

One of the big advantages of mRNA vaccines is precisely this: we can swap out the mRNA easily, allowing us to respond quickly to mutations in circulating viruses. That’s a good thing, and it might be our only path to controlling Covid-19.

The bottom line is that the new boosters should be very safe, and they will likely provide much better protection against the current strains of the Covid virus. I’ve already gotten my booster, and I hope everyone else will too.

Covid patent fight is about greed, not human health

I suppose I shouldn’t be surprised: one of the companies that developed mRNA vaccines for Covid-19, Moderna, has just sued the companies who make the competing mRNA vaccine, Pfizer and BioNTech, claiming that Pfizer/BioNTech is violating its patents.

Pfizer was surprised though, according to news reports. (Or at least they said they were.)

Moderna had announced, back in 2020, that they wouldn’t enforce patents on their vaccine during the pandemic, but they seem to have changed their mind. Apparently, billions of dollars in profits isn’t enough: they’ve decided the time is right to try to grab even more money.

Let’s make no mistake here: this is purely about greed. Apparently Moderna understands this, since they proudly advertised their earlier plans not to enforce patents on the Covid-19 vaccine. They realized that the public good will generated from such an announcement was valuable.

Not that valuable, apparently.

It’s not even clear that Moderna should have been given the patents it holds. According to a recent story in Science, the key technology behind one of Moderna’s patents was invented, and patented, years earlier by two scientists, Drew Weissman and Katalin Karikó, at the University of Pennsylvania. Their work discovered a way to modify the RNA in the vaccine that would make it much more effective. (Here’s a link to the patent.)

As I wrote last year, patenting the Covid-19 vaccine is unethical. At the time, the US had announced support for a “vaccine waiver” that would allow any country to develop vaccines against Covid-19 without licensing the technology from one of the companies that currently holds a patent. That policy sounded too good to be true–and apparently it was, because no such waiver is in effect now.

The patent system is a creation of modern governments, and they don’t have to let companies get away with this. The profits of a few companies are far, far less important than the lives of millions of people. Allowing companies to restrict Covid-19 vaccine development is, crudely put, defending money over human lives. Maybe it’s time for the international community to institute the vaccine waiver, at least until the pandemic is truly over. 

And make no mistake: even though we have vaccines now, they still need improving, and better vaccines will save lives. Patent disputes will slow down or even prevent work on better vaccines, since the patent holders will have a monopoly. Even the threat of a lawsuit can stymie progress; after all, why would someone invest time and effort on a vaccine that they might never be able to deploy?

Moderna is far from the first company or institution to let greed guide their actions: way back in 2010, I wrote about how MIT and Harvard had filed a patent that was, as I wrote at the time, both inappropriate and harmful. In that case, MIT and Harvard had an incredibly broad patent on a human gene, NF-kB, which plays a key role in our immune system’s response to infections. Granting a patent on NF-kB, as the US Patent Office did, was akin to granting a patent on all drugs that affect nearly any human gene. The universities licensed the patent to Ariad Pharmaceuticals, who filed a lawsuit the day the patent was granted. Neither Ariad nor MIT developed any treatments, but they initially won $65.2 million just because of the patent. (Need I point out that the Harvard and MIT work was mostly funded by the public?)

Fortunately, in the 2010 case, an appeals court threw out the patent, ruling that people and companies cannot patent human genes, because genes are products of nature, not inventions. The mRNA patents, though, don’t fall in this category.

Should I also mention that much of the basic research behind mRNA vaccines was also funded by the public? Or that NIH (and therefore the US government) has patent rights to some of the technology behind the Moderna vaccine?

Moderna, Pfizer, and BioNTech looked like heroes when they first announced their vaccine results–and in some ways, they were. The world was desperate for vaccines against Covid-19, and the mRNA vaccines have saved millions of lives.

But my message to Moderna is simpler: you’re already making billions in profits on the Covid-19 vaccine, so don’t be such greedy assholes. And don’t be evil: drop the lawsuit.

The mRNA vaccines are defeating COVID. Let's use them for the flu.

 

The last year has been a story of triumph in the vaccine world, with the rapid development of two highly successful vaccines for Covid-19, one developed by Moderna and the other by Pfizer and BioNTech. Now that flu season is approaching, why are we still using 50-year-old technology for the flu vaccine?

The reason the Covid-19 vaccines were developed so quickly is that they used a new, much faster and easier-to-create type of vaccine technology, based on messenger RNA, or mRNA. What’s even more exciting is that we now have an overwhelming amount of evidence, from real-world experience, that these vaccines are remarkably safe and effective.

Now, anti-vaxxers and the “vaccine hesitant” are claiming they don’t trust the vaccine because it was developed too fast. That’s ridiculous: the real reason they don’t trust the vaccine is because they’re consuming a steady diet of anti-vaccine nonsense, promoted by a combination of right-wing media and the Disinformation Dozen (who include left-wing as well as right-wing zealots). But let’s not go down that rabbit hole today.

So what is an mRNA vaccine? Here’s a brief explainer, and then we’ll look at the flu vaccine. (Note: feel free to skip ahead if you already understand the technology.)

Messenger RNA vaccines have been under development for decades, since long before Covid-19 appeared. The technology required a series of breakthroughs over the years, as described in a recent Nature news story, and many scientists contributed. It wasn’t used in vaccines in part because it wasn’t ready, but also because we rely on private companies to develop vaccines, and few of them were interested in investing in a new, not-yet-approved technology. But I digress.

Messenger RNA is the stuff that all of your cells use to translate your genes, which are encoded in DNA, into proteins. The basic process is that the DNA for a gene is copied into pieces of mRNA, where the DNA letters, ACGT, are replaced by slightly different (chemically) RNA letters, ACGU.

Every cell in your body is filled with mRNA, all the time. It’s the stuff of life, so of course it is totally safe. Each cell uses mRNA to make proteins, which do most of the actual work that keeps you alive.

Here’s the brilliant thing about mRNA vaccines: all they do is introduce some mRNA into your cells that encodes a single protein from the virus, which is called “Spike” in the case of the Covid-19 vaccines.

Your own cells then make the Spike protein, but they don’t make very much! They just make a few copies, because mRNA doesn’t last very long. And because there is no DNA copy of the Spike protein in your genome, once the mRNA in the vaccine breaks down, it’s gone forever.

The other brilliant thing is that your own immune system recognizes Spike as a foreign protein, and it generates cells that will recognize any future infections where the Spike protein is present. If you’re later infected by SARS-CoV-2 (the Covid-19 virus), your immune system is primed and ready, and in a large majority of cases it attacks and destroys the virus before you get sick.

So that’s it: an mRNA vaccine is simply a little package made of fat molecules (called liposomes) that contains a few copies of mRNA encoding a viral protein. There’s nothing to prevent us now from creating similar vaccines for the flu, or for other viruses where we need new vaccines. (In the case of flu, we can use mRNA for a gene called hemagglutinin, but again I digress.)

We make new flu vaccines every year, because the flu is constantly mutating. Most years, the flu vaccine isn’t a great match for the circulating strains of the virus, and therefore the vaccine isn’t very effective. In a good year it might be 60-70% effective, but in bad years it might be much worse. A big part of the problem comes from how we create the vaccine.

In the U.S., we make most of our flu vaccines by growing influenza viruses in chicken eggs. No, I’m not making this up. Around February of each year, a panel of experts selects 4 strains of the virus that they think will most likely match the viruses for the following flu season, which usually ramps up in November or December. (Here are this year’s choices.)

Once the experts have selected the vaccine strains, the manufacturing process begins, first by checking to see if all 4 strains will grow robustly in chicken eggs. If they don’t, the panel may have to switch to different strains that are less likely to work. No, I’m not kidding: the success of the flu vaccine depends on how well it grows in eggs. That’s one reason why, in some years, the flu vaccine is a flop. This would simply never happen if we used mRNA technology.

With mRNA vaccines, we don’t have to grow any viruses at all. The mRNA from a single gene–hemagglutinin for influenza–can simply be synthesized in large quantities, just as we’re now doing for the Spike protein in SARS-CoV-2. Or for an even more effective vaccine, we might add the gene for neuraminidase, the other protein in influenza that our immune system can “see.”

An mRNA vaccine for flu would be far cheaper to manufacture, not requiring huge chicken farms. (This year, 82% of flu doses in the U.S. were made this way.) Even more important, though, is that an mRNA vaccine for flu would likely be far more effective at controlling the severity of the infection itself.

Why aren’t we doing this already? Simply put, it’s because we rely on private companies to take the initiative, and it’s not worth it to them to test and validate an entirely new vaccine, which requires a substantial investment. There’s also a simple solution, the same one we used for Covid-19: the government should take the lead.

We’re now at the beginning of flu season, which almost disappeared last year thanks to our social distancing and masking behavior. I’ve had my flu shot, and millions more are being administered around the world. Just last week, an early report out of Europe indicated that the flu season this year might be “severe,” which is the last thing we need with Covid-19 still raging.

We don’t yet know if this year’s flu shot will be effective or not, but odds are, based on past performance, that it won’t be great. (It’s still much better than nothing, I should add.) If we want a better flu vaccine, now is the time to start developing a new one using mRNA. If private industry doesn’t step up, any one of dozens of countries have the expertise to do so instead.

Yes, we should all get boosters! Eventually.

The hubbub for the past few weeks in the U.S. has been all about whether or not the government should recommend that people get booster shots for Covid-19. Conflicting messages have emerged, with some officials saying boosters will be recommended, and others saying boosters are unnecessary or premature.

Just this past Friday, an expert panel at the FDA recommended boosters for people over 65 and for immunocompromised people, but not for anyone else.

But here’s the thing: boosters obviously help to fight Covid-19. In all the objections I’ve read, I can’t find any credible scientific or medical reason not to get a booster. All else being equal, you should get a booster vaccine, probably around 6-8 months after your second shot (if you had a 2-shot vaccine).

The confusion–and the arguments–derive from that little phrase I threw in there, “all else being equal.” You see, it’s really not controversial that a booster vaccine provides better immunity against an infection. We already have boosters for other vaccines, and there’s a wealth of very strong evidence showing that they work. For the Pfizer/BioNTech and Moderna Covid-19 vaccines, we have some early data showing that they, too, provide an excellent boost in antibody levels, which means (almost certainly) that the recipients of the boosters have better protection against Covid-19.

Indeed, a just-published Israeli study shows that in people over 60, the risk of severe disease drops nearly 20-fold and the rate of infection drops by a factor of 11 after a booster shot. (The study only looked at people over 60 because they were the only ones who got boosters.)

So yes, boosters work. The best arguments against them, scientifically, are that we don’t yet know exactly how well they work. That’s merely because these vaccines have only existed for a short time, so of course we haven’t had time to collect much data. But all the data that we do have is positive. So I’d be willing to bet a large sum of money that the evidence in favor of boosters is only going to get stronger.

But all else is not equal. What’s not equal is access to the vaccines. In the U.S., we have an excess supply, so much that pretty much anyone can get a vaccine by simply walking into one of several national-chain pharmacies, without even making an appointment. And that includes those who want a third shot (an unauthorized booster).

Meanwhile, though, many countries still face a severe shortage of vaccines. In most of Africa, for example, only 1-2% of people have received even one dose of any vaccine. Just this week, President Biden authorized a purchase of 500 million Pfizer vaccines that the U.S. will ship to other countries, and we’re going to need more. The pandemic is a worldwide crisis, and as long as the virus is circulating widely in any country, it is a threat to everyone.

Thus the argument against boosters is not a scientific one. The argument is really about where to ship the vaccines that we have. For example, as several vaccine experts wrote in this Lancet article last week, “even if some gain can ultimately be obtained from boosting, it will not outweigh the benefits of providing initial protection to the unvaccinated.”

The only problem with that statement is the use of “even if”: we already know that boosting almost definitely provides a benefit, so they should have acknowledged that fact.

So the question about boosting really should be a different one: what should the U.S. do with its abundant vaccine supply? Should it allow people to get a booster shot, which is clearly beneficial? Or should we make sure those shots go to people who haven’t yet been vaccinated at all?

It’s perfectly reasonable to argue, as some have, that we should get first shots into people’s arms before we start administering 3rd shots. If the choice is 1st shot versus booster, then yes, we need people to get their first shot. But that doesn’t justify any statements playing down the benefits of booster shots.

And is that really the choice? Well, no. At the moment, the U.S. is wasting millions of shots per month, most of them in retail pharmacies that aren’t using their full supply. The vaccines expire quickly, and it’s simply impossible to manage the supply so that all doses are used. At a minimum, we could offer the extra doses (at the end of each day, say) as 3rd shots to anyone who wants them. The alternative is to throw them away.

So to the public health authorities who are saying “no” or “not yet” to boosters: cut it out! You know very well that boosters almost certainly work, and you also know that in a year or two, we’ll likely be recommending boosters for everyone. When that time rolls around–and it will–people will be asking, quite reasonably, why you are contradicting yourself? And you can be sure that the anti-vax crowd will queue up every quote they can find in which government officials expressed any doubt about boosters.

We saw a near-identical version of this scenario play out very early in the pandemic, only then it was over masks. In early 2020, few prominent public health officials in the U.S. made ill-advised statements that people shouldn’t wear masks. They were worried that we didn’t have an adequate supply of masks, but they knew perfectly well that masks helped prevent transmission of the virus. Even so, they made statements casting doubt on masks, thinking that this would help preserve the very limited (at that time) supply. Those statements were truly damaging, and they contributed to the toxic anti-mask movement in the U.S. today.

The same thing seems to be happening again. The public health experts speaking out against boosters are worried about the supply of vaccines. So they are making statements casting doubt on the efficacy of boosters, statements that are potentially very damaging. For example, the recent Lancet piece states that “currently available evidence does not show the need for widespread use of booster vaccination.” But in the same article they admit that widespread boosting “might ultimately be needed because of waning immunity.”

Vaccine booster shots work, and the experts know it. To fight this pandemic, we need more vaccines, including boosters. We don’t need more misinformation.

The FDA needs to approve the COVID-19 vaccines. Right now.

I’ve spent untold hours fighting bureaucracy during the course of my life. Sometimes the issues are big, sometimes small, but I often get incredibly frustrated when I see organizations–and the people who work for them–enforcing rules without thinking, often to the detriment of everyone involved.

Usually, though, bureaucratic rules are little more than annoying time-wasters. They don’t usually cause actual harm to people. Right now, though, the FDA’s failure to fully approve the Covid-19 vaccines, and its rigid adherence to its own rules, is not just wasting time. It’s killing people, albeit indirectly.

The FDA needs to approve the Covid-19 vaccines, and they need to do it now. They claim to be working hard on doing just that. The vaccines have already been administered to hundreds of millions of people, and the ones used in the U.S. and Europe have proven to be remarkably safe and amazingly effective. So what is the FDA waiting for? Well, according to them, they have to wade through the paperwork.

As nearly everyone knows, here in the U.S. we have three approved vaccines against SARS-CoV-2, from Pfizer-BioNTech, Moderna, and Johnson & Johnson. The first two are messenger RNA (mRNA) vaccines, an innovative design that is strikingly effective, reducing the chance of infection by over 90%.

The U.S. now has an ample supply of vaccines, but we are struggling to get everyone vaccinated, in large part because so many people are either hesitant to get the vaccine or downright opposed. Let’s leave aside the blatant anti-vaxxers for today, many of whom are so deeply misinformed that changing their minds is probably impossible.

A much bigger problem, and one that we can fix, is the far larger number of people who are waiting for the vaccines to get full FDA approval. Not only are many individuals waiting, but many large institutions, including the U.S. Defense Department, have announced that they will mandate vaccines for their personnel once the FDA formally approves them.

Right now, the 3 vaccines in the U.S. are only conditionally approved, under the FDA’s Emergency Use Authorization (EUA). The fact sheet that the FDA provides with these vaccines includes a number of caveats, and states that “there is no FDA approved vaccine to prevent Covid-19.” That statement is not, to put it mildly, very convincing.

Full approval requires the FDA to review “hundreds of thousands of pages of documents,” a process that usually takes 10 months, or maybe six months for a “priority” application. Pfizer only submitted its paperwork on May 7, and Moderna on June 1, so even the FDA’s priority process would leave us without an approved vaccine until the end of 2021. That’s just too long.

I’ve heard the FDA’s excuses. The FDA’s Director of Biologics, Peter Marks, explained in a letter to the NY Times that

“any vaccine approval without completion of the high-quality review and evaluation that Americans expect the agency to perform would undermine the F.D.A.’s statutory responsibilities, affect public trust in the agency and do little to help combat vaccine hesitancy.”

Sorry, Dr. Marks, but these excuses are nonsense. The Covid-19 vaccines have been rolled out with unprecedented speed, it’s true, but we’re now seeing the results of a real-time, real-world experiment on hundreds of millions of people, and–luckily–the results are great! Have you and your colleagues at the FDA not noticed this?

Furthermore, everyone knows that the vaccines will be fully approved in the next few months, and multiple government officials, including the President, have said so quite openly. So why not approve them today? Because you have to follow a set of bureaucratic rules that were not designed for a pandemic?

The virus doesn’t care about the rules. Infections in the U.S. are skyrocketing again, because of the Delta variant, and the only way to end this pandemic is to get nearly everyone vaccinated. Until we have full approval of the vaccines, we’re simply not going to get there. By relying exclusively on the paperwork provided by the vaccine manufacturers, and ignoring the enormous amount of real-world data that everyone can see, the FDA is prioritizing process over results.

The FDA says that it’s now in a “sprint” to approve the vaccines, but with every day that passes, more people get sick, and the virus has more time to mutate and become more deadly.

Listen, FDA: rules are created for a reason. In case you haven’t noticed, the pandemic is a worldwide emergency that cries out for you to bend or break the rules if doing so will save lives. We all want a safe and effective vaccine, but there’s an overwhelming amount of evidence that we already have at least 3 of them (and probably 6 or 7). You can approve the Pfizer-BioNTech and Moderna vaccines today, and if new data emerges, or if you discover something startling and unexpected in those millions of pages of paperwork, you can withdraw approval. There’s nothing preventing this except bureaucracy.

So don’t tell us that you (FDA) have to “complet[e] the high-quality review” or you’ll somehow be shirking your responsibility. That response is equivalent to saying “we can’t look at the overwhelming evidence from the real world, we can only look at the paperwork that the vaccine companies provided to us.” In other words, “nanner nanner we can’t hear you” rather than considering the fact that hundreds of millions of people have taken the vaccine and that it’s working.

And about that comment from the FDA about maintaining public trust? As Dr. Eric Topol pointed out in a recent op-ed, somehow the FDA managed to approve, in the midst of the pandemic, an incredibly expensive new Alzheimer’s drug (aducanumab) for which the evidence of effectiveness is very thin, and the risks of harm are very real. The FDA’s own advisors resigned in protest, and now the FDA’s inspector general is going to take another look at how this happened. And yet the FDA is worried about “public trust in the agency”? Give me a break. Meanwhile, the FDA can’t seem to find the time to approve the mRNA vaccines “despite massive evidence of their benefits.”

The FDA needs to stop hiding behind the mountain of paperwork. Millions of people will remain unvaccinated while the FDA reviews documents that merely tell us what we already know: the vaccines work, and they are safe. Give them full approval, today, and continue to monitor their safety carefully, and many lives will be saved.

RNA vaccines have arrived. Let's starting making them for influenza, right now.

The race to end the Covid-19 pandemic will be won by vaccines. We now have at least four approved vaccines, and the first two–the fastest to be developed and approved–were both RNA vaccines, a new technology that has never before been used on a large scale.

As I’ve written before, these RNA vaccines are a scientific triumph. Both the Moderna vaccine and the Pfizer/BioNTech vaccine are 95% effective against the virus. Both were developed in a matter of days–days!–after the genome sequence of the Covid-19 virus, SARS-CoV-2, was first revealed.

Now that we know that RNA vaccines work, what’s stopping us from designing and deploying this technology for many other infections that we don’t yet have under control? Simply put: nothing. We just need to have the will to do it, and it will happen. By which I mean, we need the government to pay for it.

Once Covid-19 fades, as it will, we’ll still have to deal with influenza, which sweeps through the population every year, often mutating significantly from the previous year. That’s why we need a new flu vaccine every year: the flu itself mutates to escape the protection we have from last year’s vaccine.

(Aside: we’re in the midst of the mildest flu season in decades, perhaps ever, thanks to the Covid-19 restrictions. The CDC reports fewer than 100 confirmed cases of influenza in the entire country, at a time when we’d usually be seeing thousands of cases per week.)

RNA vaccines are remarkably easy to design, and they’re much cheaper than conventional vaccines too. We should be thinking about making them for a raft of illnesses now: not just flu, but malaria, HIV, and others. But let’s start with the flu.

We already know that we need a new flu vaccine every year, so here’s a not-so-radical proposal: let’s create an RNA vaccine for the flu, right now, paid for by the government. It’s almost certain to work, and it will likely work far better than the current vaccine. Here’s why.

For the current flu vaccines, we create a new vaccine every year based on what’s currently circulating among humans. For the Northern hemisphere, we choose the vaccine strain right around now (late January or early February), because it takes 6 months to prepare the vaccine for the following fall.

The flu vaccine production uses a crude, decades-old process. After choosing a vaccine strain, the manufacturers (GlaxoSmithKline is one) isolate the virus and then inject it into chicken eggs, where they let it grow for 4-5 days. The virus is then extracted from the eggs, killed, and stuck into a syringe. That’s basically it. (This is why people who have egg allergies are sometimes warned not to get the flu vaccine.)

There are loads of problems with this process. First, it often turns out (and this is not widely known) that the first choice for a vaccine strain doesn’t grow well in eggs. In those years, the manufacturers move on to a second, third, or fourth choice, until they find one that grows in chicken eggs. These inferior choices, in turn, lead to vaccines that are less effective at conferring immunity.

Second, the process requires huge, messy chicken farms, which means it is slow and costly. Third, even though the virus is a killed virus, there’s always a small chance that some live virus will survive and infect people.

RNA vaccines, in contrast, can be manufactured precisely to match the virus that you wish to target. There’s no need to grow it in chicken eggs. And it’s far cheaper to make. In addition, you only need a fragment of a virus to make the vaccine, so there’s zero chance that anyone can ever be infected from the vaccine. And we know exactly what to target on the influenza virus: the hemagluttinin and neuraminadase proteins that cover the surface of the virus.

If RNA vaccines are so good, one could argue, why not allow the free market to produce them? Because it just won’t happen: the flu vaccine is not very profitable, and getting an entirely new vaccine approved is very expensive. Private companies just aren’t going to do it; on the contrary, several past flu vaccine manufacturers dropped out of the business because it just wasn’t profitable.

(Interesting story: about 15 years ago, I attended a talk by Anthony Fauci about influenza. At the time, I was leading a large-scale effort to sequence thousands of influenza viruses, a project that continues to this day and that is run by Dr. Fauci’s institute, NIAID. At the end of his talk, I asked Dr. Fauci why the NIH itself couldn’t sponsor flu vaccine development. He answered that it just wasn’t done that way–that NIH handled the basic research, but left vaccine development to industry. Well, Covid-19 has changed all that.)

We don’t have to create a new government-run facility to make the vaccines in order for this to work. Instead, we can do exactly what we did for Covid-19: pre-purchase a large supply of RNA-based flu vaccines, and provide generous funding to pay for the vaccine development and testing. Then companies like Moderna and Pfizer will have proper incentives to use their technology on influenza.

The health benefits of new, better vaccines are far too important to leave this to private companies, who are motivated more by profits than by an interest in public health. Let’s use the scientific success of RNA vaccines to change the way vaccine development works in a big way. We can save untold numbers of lives if we do.

These new RNA vaccines are a triumph for science and medicine

This week the FDA approved a second vaccine against SARS-CoV-2, the virus that causes Covid-19. We now have two highly effective vaccines, one from BioNTech and Pfizer, and the other from Moderna. A third vaccine, from Oxford University and AstraZeneca, is very close to approval.

The two new vaccines, both based on RNA, are both remarkably effective. Below I’ll summarize some of the numbers, which have been published for the world to see.

This is a scientific triumph. Less than a year ago, no one outside China even knew this virus existed. The genome of the virus was first released in January, and within a few months scientists had designed the first vaccines. Clinical trials were launched immediately, and larger trials followed, leading us to where we are today: two new vaccines, tested and validated in tens of thousands of people, now being manufactured and shipped to billions.

For anyone who might be skeptical, or who just might want to know more, the test results are being published openly. The New England Journal of Medicine has a dedicated website with dozens of papers and audio summaries, including results from the large-scale (Phase 3) trials of the Pfizer vaccine.

Before getting into the numbers, let’s summarize what these two new vaccines are. (I wrote about this in July, if you want to read my previous explanation.) Both of them are RNA vaccines, which is itself a dramatic breakthrough. RNA vaccines have been discussed for years, but the technology was never employed for human vaccines until now.

Here’s how they work: our immune system (which is super-complicated, as Ed Yong explained in The Atlantic) recognizes microscopic invaders and destroys them. Once you’ve been infected with Covid-19, the immune system swarms over the viral particles and basically learns what they look like. SARS-CoV-2 has a protein all over its surface called “Spike,” so that’s what the immune system recognizes.

Once you’ve fought off the infection, the immune system remembers what Spike looks like. If you’re infected again, it can respond far more quickly, so you won’t get sick. This is what we call acquired immunity.

So for vaccines, the trick is to teach your immune system to recognize Spike. One way to do that is to manufacture lots and lots of the Spike protein, and put that in the vaccine (sort of–I’m greatly oversimplifying here).

But with modern genomics technology, we can use a different approach. Every cell in your body has machinery inside it to translate RNA into proteins. As soon as we had the SARS-CoV-2 genome, back in January, we knew the genetic code for Spike. So rather than make the protein, what if you just made the RNA, which is far easier and faster to manufacture, and injected that into people? Do our own cells then translate the RNA and make the Spike protein?

Well yes, they do. And not only that, but–as the Modern and Pfizer clinical trials have now proven–our immune system recognizes that the Spike protein is foreign (it’s complicated) and launches an attack.

So to make an effective RNA vaccine, you simply have to inject enough RNA so that the immune system responds. That’s what both the Modern and BioNTech/Pfizer vaccines have done.

Now let’s look at the numbers. As reported in NEJM just two weeks ago, the Phase 3 trail for the Pfizer vaccine tested 43,448 volunteers, of whom 21,720 got the vaccine and 21,728 got a placebo. At the time of the report, 162 people who received the placebo had become sick with Covid-19, but only 8 people in the vaccine group got sick. That’s a 95% reduction in illness, a remarkably good result. They also reported that 10 people had “severe” illness, and 9 of those ten were in the placebo group.

How about the Moderna vaccine? This vaccine has almost identical efficacy, published in a preliminary report a few weeks ago as 94.5%. Just a few days ago, an FDA review panel approved the vaccine and confirmed that its efficacy was above 94%. And the Modern vaccine doesn’t need the super-cold freezers that the Pfizer vaccine needs, which makes it easier to distribute.

Both vaccines have minimal side effects in most people, mostly soreness at the injection site, and sometimes headaches or chills, which subside within a day. RNA is quickly degraded in the body, so there’s no reason to expect any lingering side effects from these vaccines.

There’s also growing evidence that immunity lasts for many months, if not years. Another report in NEJM, on the Moderna vaccine, contains some of the latest data, which shows that immunity is still strong after 4 months. Of course, with a brand-new vaccine, we simply have to wait to see if the immunity lasts for years, but all signs are positive right now.

So yes, these are really good vaccines. I will get mine as soon as I can, although I expect I’ll have to wait several months because of short supply.

(The Oxford/AstraZeneca vaccine, a more traditional protein-based vaccine, has also shown positive results, either 62% or 90%, depending on the dosage regimen, but the 90% results are based on fewer cases. Even so, it is clearly effective and it should be approved soon, at least in the UK. So we might soon have 3 vaccines.)

A note to anti-vaxxers: no, you cannot catch Covid-19 from these vaccines. They don’t contain the virus! They only have a fragment of RNA from one protein, and the virus has RNA that encodes 28 other proteins. It’s simply impossible for the virus to self-assemble without the rest of its genome.

But hey, if you don’t want the vaccine, go to the back of the line. Most of the world is desperate for it.

The success of RNA vaccines is a huge win for science, but even more, it’s a huge win for the human population. We’re still many months away from vaccinating the whole world, but with two highly effective vaccines, we can finally have hope to end this pandemic.