Transcript for Possibility of COVID-19 reinfection confirmed, CDC shifts guidelines on testing
We turn to the latest on the coronavirus emergency and that shift by the CDC over when and if you should get tested. This as cases in colleges across the country are climbing and there are now new worries about patients becoming reinfected. ABC's Trevor Ault has the latest and this is all happening, of course, as flu season is now approaching. Reporter: Of course, Cecilia. It is a lot to juggle at the same time and there is some good news this morning that across the country in the past week the number of new cases and deaths decreased substantially but the CDC made this big change to its guidelines saying people who don't have symptoms don't necessarily need to get tested even if exposed and that's a jarring shift as a number of schools and universities report big new outbreaks. Overnight, a major change to the CDC covid-19 guidelines saying if you have no symptoms, you don't necessarily need a test, even if you may have been exposed. A direct shift from what director Robert Redfield told ABC last month. Anyone who thinks they may be infected independent of symptoms should be and should get a test. Reporter: It comes as cases rise at American colleges and universities, more than 530 at the university of Alabama, nearly 160 at the university of Missouri and even at the university of southern California where classes are mostly online, school officials are warning of an alarming increase of 43 cases in off-campus housing. People are throwing parties. I'm hoping students come to their senses. Reporter: In many school districts students are going into quarantine putting pressure on parents. They have no idea what to do. Reporter: Jennifer is the mother of a Mississippi fourth grader whose entire grade of more than 200 students is now in quarantine after multiple teachers tested positive. Jennifer is a teacher herself. She's now having to coach other parents through the virtual learning process. Parents don't understand how it works. We've had a lot of frustrations. Reporter: With the world approaching 24 million confirmed cases, scientists are studying the possibility for patients to become reinfected. In Hong Kong a patient is believed to be the first person to become reinfected with covid-19 and other cases in Europe are being investigated. This as health officials prepare for a full flu season lurking just around the corner. We've had delays. Before returning covid tests, that is not going to go away during the flu season. Reporter: And many manufacturers are trying to check for covid-19 and flu at the same time. They are not on the market yet but the flu shot is. Trevor Ault, thanks. Lots more coming up
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