Which real-world pandemic drives nearly every main storyline in Grey's Anatomy season 17?

Nearly every main storyline in Grey's Anatomy season 17 centers on the COVID-19 pandemic.

The season premiered on November 12, 2020, after production was delayed and reshaped by the real-world crisis. Rather than avoiding the pandemic, showrunner Krista Vernoff chose to begin the story during its peak, with the hospital treating overwhelmed patients and staff adapting to new safety rules.

Meredith Grey contracts COVID-19 early in the season and spends much of the story drifting in and out of consciousness, imagining a beach where she encounters characters from her past. Other characters, including Tom Koracick and Miranda Bailey's mother, are also affected. The season also connects with Station 19 through crossover plots involving the pandemic and hospital emergencies.

A common mix-up is confusing the fictional hospital's ongoing medical cases with the season's overarching real-world subject. Although the season includes storylines about racial injustice, mental health, adoption, and vaccine trials, COVID-19 remains its defining narrative framework.