When the vaccine comes, will it be final victory?

Some of the most intelligent people on the planet are making heroic efforts to develop a vaccine for the SARS-Cov-2 virus. You can find good coverage of their efforts in all the best media, New Scientist, Guardian, Mail…you name it. We know they are doing their best, but safe manufacture and production take time, and there’s no point offering an easy target for antivaxxers. Eighteen months seems a pretty good estimate, and anything that comes in ahead of that would be good indeed.

But there’s one thing that worries and concerns: could this virus mutate, and jump away from the vaccine? I am not a virologist. but here’s my scenario, for what it’s worth.

I start with that excellent site Live Science http://www.livescience.com/coronavirus. Way way back in February (seems a lifetime now, doesn’t it?) they reported how Chinese scientists in Wuhan had identified two strains of SARS-Cov 19, which they called S and L. Other experts criticised the extent to which these variations were significant, and assert that virus mutation rates are quite slow. Slow enough to ensure that a vaccine will protect a very large number of people for a very long time.

It’s certainly true that some viruses never seem to overcome our vaccine defences. As the article points out, measles , mumps and yellow fever have stayed largely under control, where a vaccine is deployed.

However, and this is where my speculation takes over, some don’t. We all have to get a new flu virus every winter. Partly this is due to a slight decline in the efficacy of our immune system. But, it’s also due to mutations in proteins in the outer coat of the flu virus, due to a process called antigenic drift. Your immune system no longer recognises the slight change in the virus, and -bingo-you either get a new vaccine or you get the flu.

Most people will object that the influenza virus belongs to the family orthomyxoviridae, whereas our friend SARS Cov 19 is in the coronaviridae family. (see Wikipedia).

Well………. The Devil whispers in my ear, thus. Both viruses have a an RNA core. They both have glycoprotein coats. The transmission mechanisms are eerily similar. So why would one mutate, and not the other? Watch this space, gentle readers. Watch this space.

en.//Wikipedia.org/wiki/coronavirus