What will this do to the economy?

When Covid-19 strikes, the worst of the damage is done by the body’s effort to fight off the disease.

The immune system can overreact in what doctors call a cytokine storm. Immune cells attack not just the viral invader but healthy tissue as well. Victims gasp for breath as their lungs fill with fluid. The novel coronavirus, which scientists have christened SARS-CoV-2, tricks us into fighting it so hard that, in the most extreme cases, we kill ourselves.

As with the body’s immune system, so with the defenses of the global economy. There’s a virtual cytokine storm going on: The all-out effort to battle the disease is doing more harm to global growth than the disease itself. Quarantines, travel restrictions, business closings, and citizens’ voluntary self-protection measures have frozen business while wreaking havoc on people’s routines.

This will be the business story of 2020: Can the world modulate its immune response so as to fight Covid-19 in a way that saves lives without damaging everything else we care about? Or is this a lost year?

There’s reason to worry that simultaneously defeating the virus and sustaining growth will be hard, if not impossible. New cases in China have declined sharply, which is wonderful news. But to make that happen the country’s leaders imposed one of the most extensive quarantines in history, corralling close to 60 million people inside Hubei province, the epicenter of the outbreak. Governments in surrounding provinces also took steps to protect their populations, enacting travel bans and forcing factories to shut down. The economic toll has been high: Growth in the first quarter will be just 1.2%, according to projections by Bloomberg Economics—the slowest year-over-year rate since China started keeping records.