The U.S. has overtaken China asthe country with the most cases in the world of the novel coronavirus, markinga new milestone in the fight against the global pandemic.

China had held the top spot since the deadly virus beganspreading there in December.

There were 82,404 confirmed infections across America,according to data compiled by Johns Hopkins University. Within six weeks, theU.S. began to see a surge in new infections and the country's first deaths.

The Trump administration is planning to issue guidelines categorizing counties across the nation as high-risk, medium-risk or low-risks, aiming to help state and local authorities decide whether to tighten or relax social-distancing measures designed to help slow infections.

China said Thursday it would close its borders to nearlyall foreigners and drastically slash international flights in a bid to curb thereintroduction of the fast-spreading coronavirus from abroad.

The country has reported a sustained decline in the numberof new domestically transmitted infections in recent weeks, even as infectionshave risen among people arriving from abroad. China had 81,782 totalinfections, according to Johns Hopkins data. Health authorities logged no newlocal infections on Tuesday and Wednesday, compared with 114 new imported casesover those two days.