Arguably the most significant science development of the last half century

It’s always hard to know how the future will judge the present. Events which utterly dominated government policy and public discourse can be forgotten in a matter of years. Other events were passed by almost unnoticed at the time, and yet – in retrospect – seem incredibly important.

So, here goes.

2020 and 2021 will be seen as a turning point. They will be considered watershed years: Before CV and After CV.

But, ummm…, the CV won’t stand for Covid or Coronavirus, it’ll stand for Conquering Vaccinations.

We’ve all had our heads so far up our collective covid backsides, that we’ve missed by far the biggest science story of the last half century: mRNA.

Let me explain. mRNA stands for Messenger RNA. This can be thought of as a “recipe book” (or programming language) for your body’s own cells. This mRNA (like a virus) enters the body’s cells and instructs them to make things. (This, by the way, is essentially how viruses work: they get our own bodies to mass produce more viral particles… which in turn infect more cells…)

We now understand mRNA well enough that we can use it to programme the body’s immune system to produce something that looks just like Covid, only without all the negative side effects or the whole self replicating bit.

This leads to extremely effective vaccines. When Oxford/AstraZeneca used a Chimpanzee virus to make their vaccine, they relied on altering an existing virus so it looked enough like Covid to fool the body’s immune system. But the tolerances are always small with this kind of approach, because the adapted virus still had to carry a bunch of genetic material related to the original (Chimpanzee) virus.

With mRNA, it was possible in just one day to produce the recipe to make our bodies create something indistinguishable to Covid from the point of view of our bodies’ immune systems.

The 12 month since then, well, that’s all been about proving mRNA based vaccines are safe for humans (they are), and building the manufacturing capability to churn out billions of doses a year.

Maybe an analogy can help make this clear.

Imagine your body’s immune system is like an iPhone with Face Unlock. The AstraZeneca vaccine was like taking a picture of the phone’s owner, printing it off, and sticking it onto the head of goat. Now, sure, the iPhone will probably unlock for the goat, but if the angle is a bit wrong, or the paper gets wet, then it isn’t going to work.

With an mRNA vaccine, it’s like you’ve created a near perfect copy of the head. Unless you notice they’re not breathing or attempt to engage that model in conversation, you aren’t going to notice they’re not real.

It is unlikely that there will be any mutation large enough to escape from Pfizer/BioNTech, Moderna and CureVac, because their vaccines are such good copies of the salient features of the Covid molecule (in particular the “spike”), and mutations are by their nature typically small. But even if they did, the scientists just need to get hold of the new mutated strain, and tweak their recipe. Only this time, we know mRNA vaccines are safe and we now have mRNA manufacturing capability.

But mRNA doesn’t stop there. It’s applications in oncology are perhaps even more important than in virology (where, by the way, it will also help defeat Ebola, HIV and others). You see, we all get tumours all the time, it’s just that our bodies recognise those tumours as dangerous and our immune systems deal with them. Cancers that kill us are ones that have managed (one way or another) to persuade our immune systems that they’re not dangerous. With mRNA we can programme our immune system to realise that growth in the lung… well, it’s something that should be removed. And all without the surgeon’s knife.

Covid has killed a few million people. But it has dramatically accelerated the acceptance of mRNA technology – perhaps by a decade or more.

In the future, Covid will be mentioned in passing, and only when describing the extraordinary story of how we conquered virus and cancers.

Robert Smithson