Over the next two months, researchers creating two potential COVID-19 vaccines hope to recruit 60,000 Americans for the final phase 3 testing. Earlier small tests showed the treatments were safe and led to participants developing antibodies against the virus. This last phase must show whether the vaccine reduces the risk of infection. But unlike most vaccine trials, where researchers have to ask 5 to 10 people just to get 1 to participate, with a COVID-19 vaccine, thousands are volunteering. Health experts hope to know if the vaccines work by this fall, allowing widespread distribution as soon as early next year.