Transcript for Coronavirus derails MLB start as cases continue to rise
Good evening and it's great to have you with us here as we start another week together. And we against tonight with the staggering spread of the more than 16 million cases worldwide now. 1 million cases in just four days. A quarter of them right here in the U.S. And the new concern tonight, the major league baseball season already altered is now under threat tonight. More than a dozen players and coaches infected with covid. And the president's national security adviser now testing positive, as well. Here in the U.S. Tonight, more than 4.2 million confirmed cases. And more than 147,000 lives now lost. Florida right behind California now with the second-most cases. Both states passing New York. The death toll now rising above 6,000 in Florida. And tonight here, the disturbing rise and what we're seeing in children in Florida, showing symptoms believed to be related to covid. Hospitals in Texas stretched to the limit. More than 5,000 lives lost in that state. And after more than a dozen marlins players and coaches tested positive, two major league baseball games involving four teams have tonight been canceled, just hours before they were to be played. So, that's where we begin tonight. ABC's Victor Oquendo leading us off from Florida tonight. Reporter: Tonight, the coronavirus derailing major league baseball's new season. This is the worst case scenario. Reporter: An outbreak on the Miami marlins. 11 players and two coaches infected, forcing them to cancel their home opener. We're taking risks every day. It's fair to say that guys are concerned. That's good enough. A missile. Reporter: The team played despite four players testing positive on Sunday. Their opponent, the Phillies, now getting tested. Tonight, their game versus the Yankees, canceled. Some questioning whether the season will have to be scrubbed. All this as the death toll surges past 6,000 here in Florida. More than 1,000 fatalities in just the past nine days. The mayor of Miami beach critical of the governor, saying the state's contract tracing efforts are failing. Did governor Desantis fail us to a certain level here in the state of Florida? There's no question the department of health, which is his agency, failed us. There's no question. Reporter: The state seeing a disturbing trend. Cases in children under 17 up nearly 8,000 in the past ten days. Covid-19 is real. It's not a myth. It's very scary. Reporter: 8-year-old Zane Wampler in the hospital for more than a week, battling that rare and dangerous covid-related syndrome in children. He spent a day on a ventilator. If I can help somebody else and other parent not go through what we've been going through -- it would be helpful. Reporter: New outbreaks nationwide. Two in New Jersey, one linked to a house party. The other to a gathering among lifeguards. At least 100 people infected total. In Alabama, 40 people testing positive after attending a church gathering. 14 family members sickened in Texas, one of them dying, after a small gathering. Covid patients making up 75% of this hospital in the hard-hit Rio grande valley. Nurses pushed to the breaking point. It's just so out of hand, you know, we see patients just dying and dying and it's, like -- when is this going to end? It's really hard. I get home and cry. It's really hard to see this. Reporter: As state after state debates keeping bars open, Dr. Deborah birx with a warning. We can see what is happening in the south moving north. We do believe that there are states that do need to close their bars, to decrease indoor gatherings to less than ten. Reporter: And tonight, new hope if the race for a vaccine. Moderna, the first company in the the U.S. Kicking off phase three vaccine trials, hoping to have it ready by the end of the year or early next year. 30,000 Americans expected to roll up their sleeves and volunteer. You're contributing to the kind of scientific advance that might ultimately save hundreds of thousands, maybe millions of lives. Reporter: Elissa green, a 66-year-old nurse in Georgia, one of the first to participate. You are not afraid, you aren't nervous, you were just eager to get in there? I was excited. I was excited. I wasn't nervous. Like I said, there's nothing live in the vaccine. So, there's nothing in it that's going to hurt me. And Victor Oquendo with us live tonight from marlins park in Miami, where tonight's home opener has been canceled. And amid this news involving players and coaching coming down with covid, also that news on the race for a vaccine, which you just mentioned there. And just moments ago, a major announcement from pfizer? Reporter: David, pfizer is ramping up to start the final stage of their vaccine trials. It would include 30,000 people. And they could start doses as early as this week. Like moderna, we could see results by October, but a vaccine would not be readily available until late this year or early next year. David? All right, Victor Oquendo from Florida tonight, thank you.
This transcript has been automatically generated and may not be 100% accurate.