Transcript for COVID-19 hospitalizations in NYC more than double in 3 weeks
And tonight here, the scene from inside hospitals from across this country. In New York city,icus are now two-thirds full. They're calling for those retired nurses and doctors. So many have returned already. Tonight, one doctor now back for a second time. And the icu nurse dying at the same hospital where he worked for 25 years. Here's our chief national affairs correspondent Tom llamas tonight. Reporter: Tonight, as cases surge, New York issuing new warnings, calling for help and fearing a return to the early and dire days of this pandemic. In New York City, hospitalizations more than doubling over the past three weeks -- the highest since June. And the mayor asking older adults and people with underlying health conditions to limit activities outside the home -- to only travel for work, school, or essential purposes. We need you. We need you if you're older, you have pre-existing conditions, to take additional precautions. Reporter: The city also asking for people who donate blood, as icus are two-thirds full. And New York governor Andrew Cuomo calling on retired health orkers to return to the front lines. Dr. Anne sacks-berg, coming out of retirement for a second time to pitch in. I wish that this -- we would recognize that we're all in this boat together. Some people die of this. And we really need to take care of each other. Reporter: Across the country tonight, the U.S. Nearing anotterrible milestone -- 100,000 people in the hospital with covid-19. And health care workers bracing for that nightmare enario, a surge upon a surge. We're all very tired. I'm very tired. We're preparing for the worst. It doesn't get easier. Reporter: In Reno, Nevada, Dr. Jacob keeperman posting this photo, saying he'd seen five deaths in the previous 32 hours. We at some point might get to a breaking point. Reporter: And still, some medical workers are paying the ultimate price. Gary Woodward worked as an icu nurse in Nashville for 25 years. He had a passion for caring for his patients. Reporter: Woodward dying Saturday at the same hospital he worked for for so long. His family was his all. Everything we did, we did together as a family. And he was our roc and that rock is gone. We're thinking about all these families and that dedicated nurse. Let's get right to Tom, back with us tonight. And Tom, I know there's a new study out tonight, finding that the virus might have been here in the U.S. Many weeks earlier than thought, as early as mid-december last year and I know they looked at blood donations collected by the American red cross, they found antibodies for covid-19? Reporter: That's right, yet another study that showed the coronavirus was spreading around the world and even here in the United States well before public health officials new something was going wrong. And as you mentioned, study came from the CDC, it showed Americans had the coronavirus sometime in mid-december of 2019. And David, some of the states where they found it may surprise our viewers. Places like Michigan, Iowa and
This transcript has been automatically generated and may not be 100% accurate.