Preliminary dataexternal icon from mRNA COVID-19 vaccine trials indicate that most systemic post-vaccination signs and symptoms are mild to moderate in severity, occur within the first three days of vaccination (the day of vaccination and following two days, with most occurring the day after vaccination), resolve within 1-2 days of onset, and are more frequent and severe following the second dose and among younger persons compared to those who are older (>55 years).
Cough, shortness of breath, rhinorrhea, sore throat, or loss of taste or smell are consistent with post-vaccination symptoms, and instead may be symptoms of SARS-CoV-2 or another infection.Because systemic post-vaccination signs and symptoms might be challenging to distinguish.