Prepare for fevers, headaches and pain in the arm.
In the U.S., there are four companies that are in the final stage of testing their COVID-19 vaccines: Moderna, Pfizer, AstraZeneca and Johnson & Johnson. All of them have reported side effects in trial participants after giving the shots. Two companies—AstraZeneca and Johnson & Johnson—have paused phase 3 human testing in the U.S. after several volunteers fell so ill that it worried health regulators.
It’s not uncommon for vaccines to induce adverse responses in healthy people. Most of them will still make it past the FDA as long as the discomfort is mild and temporary. Yet, it’s something the public needs to know before taking any vaccine, especially one for a highly contagious virus like COVID-19, which would require vast adoption to stem its spread.