Clinical trials showed that the Moderna COVID-19 vaccine is safe; its side effects are mostly mild
The Moderna COVID-19 vaccine may cause mild and short-lived side effects such as fever, headache or fatigue. None of these effects have long-lasting consequences. Severe allergic reactions to the vaccine may occur, but these are rare and can be treated. Vaccination has been effective in eradicating polio from the vast majority of developing countries, preventing an estimated 16 million cases and 1.5 million deaths worldwide. While vaccine-derived polio cases do occur, they are very rare and can be avoided by improving sanitation and vaccine coverage in vulnerable communities.