Covid-19 cases are climbing in more than half of US states and these factors helped drive the surge

And there's several factors that got the country here, one expert told CNN.

Among them are college and school reopenings, Dr. Tom Inglesby, the director of the Johns Hopkins Center for Health Security, told CNN Monday night. But that's not all.

 

"I think there's some, what people might say, pandemic fatigue, in some places people not really following the advice, the public health guidance that's out there -- masking, or distancing, or telecommuting. There's more people going back to large gatherings, family gatherings."...

 

At least 12 states reported their highest seven-day average of daily cases Sunday, according to data from Johns Hopkins University. Meanwhile, the nation's seven-day average climbed to more than 56,000 cases -- a level not seen in the past 12 weeks. And on Friday, the US reported the most new infections in a day since late July.