Vox: “Two highly effective Covid-19 vaccines are now being administered across the United States, and more are in the pipeline. Almost 2 million people have already received the first of two doses of these vaccines, and officials are aiming to immunize one-third of the US population by the end of March 2021. It’s a stunning accomplishment for a disease that was barely known to the world a year ago, and it means that an end to the crisis is in sight. Yet the US remains in the worst throes of the pandemic to date, with hospitalizations and deaths continuing to break records. Vaccines are critical in drawing down the pandemic as we know it, but it won’t be a simple return to the world before Covid-19. It will likely be a process that lasts several months, and precautions like social distancing and wearing masks will still be needed until there is widespread immunity to the virus. “It’s a bit of a glide path in my mind toward a new normal, and a new normal that will continue to get better and better,” said Ashish Jha, dean of the School of Public Health at Brown University. “Ultimately, the mental model that I’m going for is ‘When are people going about their day and not thinking about Covid?’” Exactly when and how this will happen hinges on several key variables relating to vaccines that scientists and health officials are still trying to sort out. The vaccines being administered right now — the Moderna vaccine and the Pfizer/BioNTech vaccine — have only received emergency use authorizations, not full approval, from the Food and Drug Administration. Regulators have determined that the benefits of the vaccine outweigh the risks for most adults at high risk of exposure, but there are still some unanswered questions, such as how long protection lasts, and how well these vaccines block transmission of the virus between people. And beyond the vaccines themselves, how quickly and how readily people accept them can change the course of the pandemic…”