United States on Saturday notched a record number of Covid-19 cases in a span of hours, reaching nearly 230,000 new infections, a tally by Johns Hopkins University showed on Sunday.The country reported 2,527 coronavirus-related deaths, according to real-time data provided by the Baltimore-based university at 8:30 pm (0130 GMT Saturday).The United States -- the country with the most coronavirus cases and deaths in the world -- has seen a dramatic resurgence in its epidemic in recent weeks.US health officials warned of a surge after millions of Americans traveled to celebrate last week's Thanksgiving holiday despite pleas from authorities to stay home.For two weeks, the US has regularly topped 2,000 deaths per day, as it had in the spring at.