Countdown to America’s first coronavirus vaccine: What to watch this critical week

For a nation ravaged by the pandemic, this week marks a pivotal moment — the final push by federal regulators to clear the first experimental coronavirus vaccine for a besieged populace.

If all goes as expected over the next few days, the Food and Drug Administration could give emergency authorization to the vaccine as early as week’s end, triggering the start of an unprecedented effort to inoculate enough Americans to confer individual immunity and eventually stop the virus’s spread. That next chapter, however, is filled with herculean challenges, including ramping up production to tens of millions of doses, shipping them in specially designed boxes packed with dry ice to keep them ultracold and vaccinating people in every corner of the United States.