Virus keeps spreading as schools begin to open, frightening parents and alarming public health officials

Mississippi, now experiencing the country’s highest rate of positive tests, is emblematic of the pandemic’s new reality. The virus is no longer principally an urban problem: It is present throughout every state, and those infected often don’t know it, leading to what top public health officials call “inherent community spread.”

This has proved true for Ohio Gov. Mike DeWine (R), who learned he had the novel coronavirus when he tested positive Thursday morning in advance of a planned meeting with Trump. Trump went ahead with his visit to a Whirlpool plant; DeWine, the second governor known to have contracted the virus, went into self-isolation. Later Thursday, DeWine tweeted that a subsequent test had come back negative.

The situation in Mississippi is unfolding as well in other largely rural parts of the country, including in Alabama and California’s Central Valley, places where so much viral material is circulating that when people get infected, many are unsure when or how it happened — so the outbreaks cannot be easily traced and contained....