Transcript for 1st documented COVID-19 reinfection identified in the US
We're going to turn to the coronavirus in the U.S. And the new and alarming headline. We have seen it in oh countries and now what's believed to be the first case of reinfection in the U.S. Reporter: Tonight doctors in Nevada confirming the first known American to be reinfected with the coronavirus. The 25-year-old man first got sick in March, but recovered, even tested negative twice. But 48 days after the initial infection his symptoms returned, he had to be hospitalized. This time, with a different strain of the virus. There's a danger even if you've had it, your immune system won't protect you from a significant illness the second time. Reporter: It comes as crowded scenes like these are shared on social media raising alarms. From this college party in Georgia to a rave in New York. Tonight, a new crackdown in Los Angeles. The city filing criminal charges against two tiktok stars for hosting these packed house parties in defiance of local health orders. If you have a combined 19 million followers on tiktok in the middle of a public health crisis, you should be modeling great behavior, best practices for all of us rather than brazenly violating the law. Reporter: Bryce hall and Blake grey could face up to a year in jail. Before being charged, hall told TMZ he immediately regretted it. Was not expecting that many people to come. It happened. Our power got shut off. I deserved it. Reporter: And, David, tonight, there is more pushback and downright outrage from thousands of local health officials over those new CDC guidelines that say, if you have been exposed but don't have symptoms you don't need to get tested. They cite the CDC's own data that suggests up to 40% of covid cases are due to asymptomatic transmission. More to come on that, I'm
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