The number of novel coronavirus cases in the United States has topped seven million - more than 20 per cent of the world's total - as Midwest states reported spikes in infections in September.
The latest milestone comes just days after the nation surpassed over 200,000 COVID-19 deaths, the world's highest death toll from the virus. Each day, over 700 people die in the United States from COVID-19.
According to a Reuters analysis, positive cases rose in half of the 50 US states this month. Ten states have reported a record one-day increase in cases in September.
New cases rose last week after falling for eight consecutive weeks. Health experts believe this spike was due to reopening schools and universities as well as parties over the recent Labor Day holiday.
A study by researchers from the University of North Carolina at Greensboro, Indiana University, the University of Washington and Davidson College said recent reopening of college and university campuses for in-person instruction during late summer this year could be associated with more than 3000 additional cases per day in the US in recent weeks.
US confirmed cases are the highest in the world followed by India with 5.7 million cases and Brazil with 4.6 million.
The US is averaging 40,000 new infections per day. Top infectious disease expert Dr. Anthony Fauci has said he would like to see the number to fall below 10,000 per day before flu season starts in October.
Health officials and President Donald Trump have presented different views about the nation's health crisis.
Trump, who is seeking re-election to a second term on November 3, early this month had claimed that the United States was "rounding the corner" on the crisis.
Fauci contradicted the claim the next day, saying the statistics were disturbing.