Two of the principal U.S. coronavirus hot spots - New York and Louisiana - reported their biggest jumps in COVID-19 deaths yet on Friday, as the White House sent mixed messages on whether Americans should cover their face if they venture outdoors.

Surging deaths in New York City and New Orleans showed that a wave of lethal coronavirus infections expected to overwhelm hospitals, even in relatively affluent, urban areas with extensive healthcare systems, has begun to crash down on the United States.

Governors, mayors and physicians have voiced alarm for weeks over crippling scarcities of personal protective gear for first-responders and front-line healthcare workers, as well as ventilators and other medical supplies.