Will we need to make new coronavirus vaccines each year? Will it change "just like the flu"?

Probably not. Coronaviruses and influenzas are very different in how they infect human cells, which impacts our ability to make effective treatments, mutations or not.

Here's why/how.

Coronaviruses have pandemic potential because of their spike proteins. SARS, MERS, and the current SARS-CoV-2 share similar spike proteins, which are displayed on the viral envelope ("the surface", these are surface proteins) and attach to certain human cells.

Yes, the spike protein can mutate and is mutating. But even current vaccines are likely to provide some level of protection against new strains. Although we might need to formulate a new vaccine here and there, we should be able to give enough people enough immunity.

Seasonal influenza (aka "the flu") is different.

You've probably heard of H1N1 (the recent "swine flu"), H3N2, and others over the years. Well, "H" and "N" stand for hemagglutinin and neuraminidase. These are surface proteins for influenza viruses.

But...

There are 18 different subtypes of H and 11 different subtypes of N. There are 198 different possible combinations HxNy for influenza (we've only seen 131 of these in nature).

Each year, a handful of these subtypes circulate to create flu season.

While influenzas mutate, it's not quite accurate to say "we need flu shots each year because the flu mutates". The reason we need flu shots each year is because of the incredible diversity of surface proteins.

You could live to be 130 years old and see a new strain each year!

Coronavirus, on the other hand, has one spike protein.

Yes, it'll mutate. Yes, we'll probably need to provide vaccines to humans born after the pandemic.

But we can almost certainly crush coronaviruses into submission with a vaccine or three.

Maybe offshoots of SARS-CoV-2 will circulate seasonally, or just fade into the background of cold season (coronaviruses are part of that, too).

But we probably won't need new coronavirus vaccines each year. Coronaviruses and the flu are very different.