One of the mysteries in how badly Covid-19 hammered Michigan is the fact that C-19 homed in on Detroit like a heat-seeking missile.
How did it make the jump from Wohan to Detroit and seemingly skip over the most likely, intermediate steps (U-of-M is in Washtenaw county, MSU in Ingham)?
One possibility is that virtually all employees in Detroit Metro Airport are both residents of the City of Detroit and belong to "economically disadvantaged minorities".
Every ticket-taker. Every custodian. Every person working in a shop or handling luggage.
So rather than fanning out through the suburbs, where most Chinese nationals live, it vectored into the inner City where the Detroit Metro Airport workers live.
Just a hypothesis. Detroit got hammered by over-zealous "Affirmative Action".