As Latin-American countries have started easing down on the lockdown measures, the chance for a second wave of infection demands strict and rational control policies to keep fatalities minimized. A part of the hopes of the population to return to normality centers on the development of a vaccine that provides immunity, because despite the fact that a typical vaccine takes years to be developed, those that are being designed for this pandemic advance to a pace never seen before. However, for both the scientific community and public health officials, deciding when a vaccine will be ready for mass release to the public is a delicate balancing act.