More than 40,000 new cases of COVID-19, a record total for the second straight day, as a nationwide sense of urgency grew and caseloads soared in Southern and Western states that were far removed from the worst early outbreaks. Thursday’s record came as at least four states — Alabama, Alaska, Montana and Utah — reported their largest daily totals. California, where stay-at-home orders were imposed particularly early, surpassed 2,00,000 cases on Thursday, as its number of infections doubled over the past month.

In a trend that has alarmed health officials and prompted renewed pleas for masks and social distancing, younger people are making up a growing percentage of the new cases. In Arizona, people ages 20-44 account for nearly half of all cases. In Florida the median age of residents testing positive has dropped to 35, down from 65 in March. And in Texas, where the governor paused reopening on Thursday as hospitals grow increasingly crowded, youngsters now account for the majority of new cases.

The pattern is drawing notice from mayors and governors. The rise in cases among younger people could complicate the plans to open schools and universities. Florida governor said he did not intend to move to the next phase of reopening. The Trump administration is also discussing a major change in testing strategy — a shift to “pool testing”, in which samples from many people are tested all at once in an effort to quickly find the infected and isolate them. US’ top expert Anthony Fauci said the White House task force is also mulling ways to beef up contact tracing, so that it is done not in phone but in person, by people who can persuade those at risk to isolate themselves.