Deaths from the coronavirus in the U.S. have passed 100,000, according to a Times database.
Disney announced that its Florida theme parks would reopen in mid-July.
California became the fourth state with at least 100,000 known cases.
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Scores of deaths, and still so much to learn

This afternoon we received a grim note from Mitch Smith, one of the reporters who keep track of The Times’s database of coronavirus-related deaths: “We crossed 100,000 known deaths at about 3:40 E.T. with new data from Illinois.”

One hundred thousand deaths. It’s a staggering toll, larger than the number of American casualties in every military conflict since the Korean War. As we pass this milestone — one that, just last month, President Trump predicted we would never reach — we are reminded how quickly this all happened, and how incomplete our knowledge of the virus remains.

A new study revises the timeline for when the virus began to spread in the West. According to an analysis of the virus’s genome, the earliest known infections in the United States and Europe petered out before they could ignite outbreaks. Instead, the study says, the pandemic was seeded weeks later by a different set of infections.

Carl Zimmer, who writes about science for The Times, said the study demonstrated that most people who get the virus do not end up passing it on; rather, outbreaks stem from a small number of super-spreaders.

“The virus probably arrived a number of times in the United States, before the virus showed up that really set off some of these big outbreaks,” Carl told us.

If correct, the study backs up what public health experts have been arguing for months: that in order to identify the people who could become super-spreaders, we needed rigorous contact tracing and testing early on.

“If there had been large-scale testing in the United States, as there was in South Korea, we could have seen these little sparks of the virus showing up and could have kept an eye on them to see if any were leading to outbreaks,” Carl said. “Instead, scientists are having to be historians now.”