(CNN) Nearly 30 US states are reporting downward trends in Covid-19 cases , but the pandemic will likely worsen again, according to the country's leading infectious disease expert. "We need to hunker down and get through this fall and winter because it's not going to be easy," Dr. Anthony Fauci said Thursday. A new study says the US greatly undercounted Covid-19 cases at the start of the pandemic -- missing 90% of them -- mostly due to a lack in testing. Infected college students shouldn't be sent homeColleges across the country have made face masks a requirement hoping to keep Covid-19 cases down. And more than 1,300 Arizona State University students have tested positive for the virus since August 1.

Source: CNN September 11, 2020 07:07 UTC