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mRNA vaccine side effects

The potential side effects and long-term consequences of mRNA COVID-19 vaccines, including the persistence of vaccine mRNA or spike fragments in tissues.

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Jan 24, 2026
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Do mRNA vaccines modify the spike protein sequence compared to the virus (e.g., prefusion stabilizing mutations) and when were these first used (2020)?

do not encode an unmodified, wild-type viral spike sequence; manufacturers intentionally altered the spike open reading frame to improve stability and antigenicity — most notably by introducing prefus...