Transcript for New model predicts Chicago, Baltimore and Boston could become COVID-19 hotspots
And all of this amid a new and dire warning about masks in this country. Troubling new signs of a possible resurgence in some of America's largest cities. And a growing risk in college towns this fall. And the numbers tonight. 24 states still seeing deaths on the rise. More than 165,000 lives lost. Tonight here, the worries over schools. How to open safely. A second high school in Georgia cloegsing for two weeks now, nearly 1,200 students and staff in that district alone are now in quarantine already. And tonight, new and strong words from the head of the CDC about wearing masks. Saying he is not asking some to wear them, that we all have to. Or that this fall could be the worst we've ever seen. Here's ABC's Matt Gutman. Reporter: In Arizona, a state battered by the virus, parents and students demanding in-person classes. Only when it's safe! Then don't get paid at all. They're teachers. This is their job. And this is what they need to be here to do. Reporter: But teacher Brad Charles has diabetes and worries about the risks of getting covid. I feel like, in a way, they've made us enemies. Reporter: And he's calling it quits. I've resigned as of yesterday. Reporter: In borne, Texas, it was the first day back to school. Students separated by plexiglass and all teachers and students required to wear masks. But in cherokee county, Georgia, nearly 1,200 students and staff are quarantined after dozens tested positive. Two high schools closing for two weeks. Another Georgia high school, where these images of students without masks ignited a heated debate, now has 35 people testing positive. Students protesting a school board decision to switch to partial online learning. We shouldn't be forced to go online because others are fearful. Reporter: And tonight, the CDC director urging every American to wear a mask. I'm not asking some of America to do it. We all got to do it. Reporter: Warning of the consequences. If we don't do that, as I said last April, this could be the worst fall, from a public health perspective, we've ever had. Reporter: When David asked Dr. Anthony Fauci about those images of students without masks -- There should be universal wearing of masks. When I see sights like that, it is disturbing to me. Reporter: New cases down in 49 states. In California, one hospital system taking matters into its own hands. Because sending tests to outside labs can take so long to get results, hospitals like this one, Providence St. Joseph, have spent enormous resources on obtaining machines like this, which can process up to 900 covid tests every day, all of it in-house. Is but tonight, a new model predicting places like Chicago, Baltimore and Boston could be emerging covid hot spots. This virus is still here and very much present. And that's our reality. Reporter: In New York, police now investigating after this video emerged a group of young people took over a city bus, turning it into a party. No masks in sight. Across the river in New Jersey, where the governor called for schools to reopen, but hundreds of teachers refused to return to the classroom, tonight, the governor relenting, allowing schools the option of going all virtual. There is no one size fits all plan to this very difficult situation. Reporter: David, here in California, hospitalizations are down 20%, prompting the governor to proclaim that the state has turned the corner on the pandemic, but they're not quite ready to open up all schools like the one behind me yet. That, with a 150% of covid cases in children and teens just over the last month. David? All right, Matt Gutman. Great to have you with us
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