Masks do work, but mask policies are another thing entirely.

The use of masks to prevent the spread of Covid-19 has been controversial almost since the beginning of the pandemic, two years ago.

The U.S. Surgeon General made a huge early blunder, in February of 2020, when he recommended against masks, tweeting that

“masks are NOT effective in preventing general public from catching #Coronavirus, but if healthcare providers can’t get them to care for sick patients, it puts them and our communities at risk!”

That self-contradictory tweet was later deleted, but it caused a tremendous amount of confusion. After all, if masks don’t work, then why is it so important that healthcare workers have them?

Masks do work. The evidence is overwhelming that masks, if properly worn, “substantially reduce exhaled respiratory droplets and aerosols from infected wearers and reduce exposure of uninfected wearers to these particles,” as described in a CDC publication last year.

The idea that masks should help prevent infections is intuitively obvious: Covid-19 spreads through the transmission of viral particles from an infected person. These particles travel through the air, as numerous studies have shown, just like many other infectious diseases. If you can stop the spread of the viral particles themselves, then (obviously) you stop the virus from infecting people.

However, evidence emerged early on in the pandemic that cloth masks and standard surgical masks were not very effective, because they allowed viral particles to leak out (and in). The SARS-CoV-2 virus is really tiny, and it can slip through the gaps in these masks.

In other words, some masks work better than others.

In June of 2020, a large study published in The Lancet reported that N95 masks were far superior at preventing transmission of Covid-19. That study found that “face mask use could result in a large reduction in risk of infection, with stronger associations with N95 or similar respirators compared with disposable surgical masks.” They reported an overall risk reduction of 85%, with N95 masks conferring a 96% reduction but surgical masks just 67%.

It’s easy to find studies showing how to make masks even more effective: make sure they fit very snugly, tightening them around the head or ears if necessary. Medical professionals who follow these guidelines have had very few infections, despite being exposed daily to sick patients. (Johns Hopkins Hospital, part of my own university, has reported almost no infections among its medical staff caused by exposure to patients.)

This all makes perfect sense. After all, if masks didn’t work, then doctors and nurses would have to be unbelievably self-sacrificing (even more than they are already) to treat Covid-19 patients. Fortunately, though, a properly worn N95 mask does an excellent job at protecting the wearer against infection.

One problem that often goes unmentioned, though, is that the better the mask, the harder it is to breathe. This too is pretty obvious: if you make it harder for tiny particles to get in or out, then of course it’s harder to breathe. Snug-fitting N95 masks are, simply put, uncomfortable.

Mask policies are the real problem. Even though masks work, getting millions of people to wear them, and wear them consistently and properly, is a far greater challenge. A casual stroll through any indoor space where masks are required–and we’ve all done this–will reveal many people whose masks don’t cover their noses, or whose masks are clearly very loose, or who might not be wearing masks at all, despite the rules.

Why don’t people wear their masks? This too shouldn’t be a mystery. Many people, young and old, simply don’t like being told what to do, so when a local government says they have to wear masks, they resent it. And governments (or large companies) have a habit of creating one-size-fits-all policies that are don’t make sense for some people. The simplest mask mandates (simplest to explain and enforce, that is) say that everyone should wear a mask all the time, or that everyone should wear a mask indoors.

For example, in Baltimore everyone has to wear a mask indoors, but restaurants are open. Thus diners must wear a mask from the entrance to their table, and then they can eat their dinner, mask-free, for as long as they wish. This doesn’t make much sense.

And what about people who are vaccinated and free from any Covid-19 symptoms? Nope, no exceptions, according to every mask mandate I’ve heard of. Naturally, that is frustrating to some people. No one should find this surprising.

In reaction to mask requirements, many people, particularly on the political right, have proclaimed that “masks don’t work.” While some of them might believe this–in which case they are just wrong–what they might really be talking about is masking policies, and in that sense they are right. If you can’t get nearly everyone to wear an N95 mask, then you can’t realistically control the spread of the virus.

We’ve seen how this works in the U.S.: despite widely varying mask policies, the Omicron variant has swept through every single state in the country, including those with strict mandates. Some places, like New York City, were hit earlier despite having fairly strict mask policies. States with no masking requirements and those that banned mask mandates (such as Florida, Georgia, South Carolina, and Tennessee), were hit later and just as hard.

One reason that masking policies don’t work–although masks themselves do work–is that it’s just really inconvenient to wear a mask all the time.

So people continue to wear masks badly, or to refuse to wear them at all. Does this mean we should give up? No, not exactly. But we might have to limit strict masking rules to places where truly vulnerable people are present, such as hospitals and senior care homes. Large-scale mask mandates are just not working, and there’s probably little we can do to change that in a free society.

A far, far more effective way to control the virus is through vaccination. As Eric Topol pointed out recently with an elegant graphic: “How to reduce your chance of dying from Covid by 99%? Get vaccinated and a booster.”

Patenting the Covid-19 vaccine is wrong

The world has recorded at least 166 million cases of Covid-19 and over 3.4 million deaths, according to the Hopkins coronavirus dashboard, and the true numbers are certainly far higher. The only way we will defeat this virus is through vaccines, and fortunately science has delivered the goods, with multiple highly-effective vaccines now being produced. In some countries we are turning the corner: in the U.S. cases have been steadily declining since mid-winter, and are now at their lowest level since last June.

Unfortunately, in many countries the virus is raging unchecked, and vaccines are in very short supply. We won't defeat SARS-CoV-2 until the whole world has adequate supplies of vaccines.

One barrier to wider, more rapid distribution of vaccines is patents. The companies that are making the vaccines have patents on them, which means that no one else can manufacture the vaccines without paying license fees. 

The human species doesn't have time for this nonsense. The profits of a few companies are far, far less important than the lives of millions of people. And yet many governments, including most EU countries, are standing firm behind the patent system. Crudely put, they are defending money over human lives. 

Recently, in a surprising move, President Biden 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. The UK is now considering supporting a waiver as well, but other countries in the European Union and the G20 have come out against any waivers. The EU position seems to be that if you can't pay, you can't have the vaccine, even if your own scientists have the expertise to manufacture it themselves.

I've been an outspoken critic of patents for many years, including gene patents (which never should have been allowed in the first place) and software patents (which are frequently filed for trivial ideas and often used primarily to create lawsuits), but patents on the Covid-19 vaccine are objectionable for a different reason: they're unethical. If companies persist in enforcing them, the governments that approved the patents should simply invalidate them.

I know that many people will tell me I'm naive for suggesting this. I have heard their arguments before, many times. These include claims that without the patent system, companies simply won't invest in new inventions, and the public will suffer. These claims are, bluntly put, wrong.

In a famous 1955 interview, Jonas Salk, the inventor of the polio vaccine, was asked by journalist Edward Murrow who owned the patent. 

“Well, the people, I would say," Salk replied. "There is no patent. Could you patent the sun?" 

And yet despite not being patented, the polio vaccine was successfully produced and distributed, and as a result humans have essentially eliminated polio from the world. (It still persists in a handful of countries, due to political and economic reasons as well as vaccine resistance.)

Just a few days ago, epidemiologists Gregg Gonsalves and Gavin Yamey (from Yale and Duke) published a public call for a "people's vaccine," which would require waiving patent rights on Covid-19 vaccines. They point out that vaccine waivers are just one step among several that we need to take, as a species, if humans are going to defeat this pandemic. So if I'm naive, I guess I'm in good company.

Why do we have the patent system at all? When you think about it, the patent system is a government-supported, guaranteed monopoly on a commercial product. The only possible reason for governments to support this is that the citizens of their countries will benefit. The patent system was never designed to guarantee the profits of private corporations and law firms–but of course these groups have profited immensely from patents, and they have created an entire ecosystem to defend the status quo.

But I digress. The Covid-19 pandemic is a worldwide health crisis that surpasses anything we've seen since the 1918 influenza pandemic. Stopping the pandemic, and ending the suffering and death of millions of people, will require getting vaccines into most of the world's population, whether they live in rich countries or poor ones. Patents and the licensing fees that come with them can only slow down this process.

That's why enforcing patent protection on any Covid-19 vaccine is unethical. The companies that are claiming patents could fix this by announcing that they will offer their technology for free to anyone in the world, but we can't expect that to happen. President Biden's announcement that the U.S. supports a patent waiver, and the UK's likely announcement of a similar position in the coming days, are a great move in the right direction. Let's hope that the rest of the world's governments follow suit.

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.