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Index/Topics/Vaccine adverse reactions

Vaccine adverse reactions

Common and rare adverse reactions to COVID-19 vaccines, including cardiovascular and hematologic events

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2 results
Jan 15, 2026

What mechanisms could explain transient ALT or AST elevations after vaccination with mRNA vaccines?

Transient elevations of ALT and AST after mRNA COVID-19 vaccination have been reported rarely and are usually self-limited; proposed mechanisms include innate immune activation by mRNA and lipid nanop...

Jan 9, 2026

What are the most frequently reported adverse reactions to mRNA vaccines in clinical trials?

Clinical trials and early observational analyses consistently show that the most frequently reported adverse reactions to mRNA COVID-19 vaccines are local reactions—chiefly injection‑site pain—and tra...