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.

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