How mRNA vaccines work, oversimplified:
It's a mRNA string that instructs yr own cells to create a spike protein that is highly similar to the spike protein outside the SARS-COV-2 virus. This is the new part. The mRNA is gone in hours, & the spike proteins are gone in days.
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Yr immune system sees the spike proteins, & develops immunity to them. That's the part that's like any other vaccine (& a lot like any actual infection too).
Later on, if & when yr immune system sees SARS-COV-2 spikes, it attacks. That's how all acquired immunity works.
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