New York Gov. Andrew M. Cuomo (D) confirmed the state’s first case of coronavirus Sunday night, announcing that a woman in her late 30s contracted the virus after traveling to Iran. President Trump on Saturday extended a travel ban on Iran to apply to any foreign nationals who had been in that country over the past 14 days.

Also on Sunday, Washington state reported its second death in King County, which is also the second death in the United States.

The coronavirus has probably been spreading undetected for about six weeks in Washington state, where the first U.S. death was reported this weekend, according to new research. A genetic analysis suggests that the cases are linked through community transmission and that the virus is likely to have been spreading undetected for weeks, with hundreds of infections possible in the state.

Officials in the Seattle area are monitoring a possible outbreak at a long-term nursing home. The elderly are considered especially vulnerable to infection. One patient is a health-care worker in her 40s who was in satisfactory condition, according to state health officials. The other, a resident in her 70s, is in serious condition.

The global death toll has surpassed 3,000 on four continents. The first U.S. death, in Washington state, was a man in his 50s with underlying health conditions, officials said. The patient had no recent travel history or contact with people known to be infected, officials said.

Here are the latest developments: