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14th Dec 2021

Why do Covid boosters work if two vaccine doses don’t?

Danny Jones

Omicron is spreading, the booster campaign is important – here’s why

As Covid-19 cases continue to increase across Europe and the rest of the world and the highly-transmissible Omicron variant is beginning to set down roots in the UK, the already planned Covid booster campaign is more important than ever.

Whether it’s those who are anti-vax, sceptical, or at the very least questioning why a third jab is needed after the first two doses of the vaccine, as the BBC has reported, Covid boosters are being put in place to help protect you against other variants.

While two doses of most vaccines could offer you over 80% protection from the original SARS-CoV-2 that started the pandemic back in late 2019, and similar protections against the Delta variant, some doses could offer limited protection from contracting Omicron.

We knew that we were going to need boosters ages ago, as scientists revealed that the effectiveness of a jab decreases after six months – for the very same reason you need a flu jab every year. Here is a helpful little guide on booster jabs from back in August:

Although it is not yet fully known if the new strain causes any more severe symptoms or health risks, what we do know is that is more transmissible than standard coronavirus – more so than the Delta variant as – simply due to how viruses work.

The options among our current vaccine programme were all developed to resist the first form of the virus that emerged more than two years ago. Covid-19 as we know it now has at least five different variants and the antibodies you gained either from an infection, your vaccines or both, are less and less effective as the virus learns how to fight it.

Like most viral infections, including those belonging to the SARS or influenza, they have the propensity to mutate and spawn new variants that fight off previous vaccinations and immunisations.

This happens all the time and just like with common colds and the flu, this is why we cannot invent a cure: because they simply adapt too frequently and continue to respond in kind every time it encounters a new jab.

Covid-19 spike proteins

No immunisation will ever cure you from getting the sniffles and a chesty cough but it doesn’t stop a lot of people from getting one, does it? For those less convinced by Covid boosters but who still get a flu jab, this should be a pretty easy one to figure out.

The good news is that antibodies evolve too and do so faster and more effectively whenever they’re given new information via the likes of a vaccine. Moreover, not only do booster jabs give you better antibodies that are learning just as quick as the virus is, but a third dose will give you even more of them. Quality and quantity.

Lastly, the better the antibodies you have, combined with the more of them there are in your system, the better your body’s immune memory is. In short, this means you will continue to produce antibodies that not only help you fight off both current and hopefully future mutations, but prevent the serious health problems that can be caused should you still contract the virus.

Nobody is trying to micro-chip you or change your DNA; it doesn’t make you infertile and there’s certainly no 5G conspiracy: ‘They’ are literally just trying to keep people healthy and stop those at risk from dying – it’s really not that complicated.

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