President-elect Joe Biden unveiled his health team on Tuesday, warning Americans of a “dark winter” but promising to “change the course” of the pandemic within the first 100 days of his administration by reopening schools, requiring masks and offering 100 million vaccinations. “All I can tell you is the truth: We’re in a very dark winter,” Biden said Tuesday in Wilmington, Delaware. “We did not get into this mess quickly, we’re not going to get out of it quickly, it’s going to take some time, but I’m absolutely convinced that in 100 days we can change the course of the disease.” The president-elect struck a somber tone, at odds with President Donald Trump’s frequent dismissal of the severity of the virus. Biden warned there was no quick fix. He promised his administration would administer 100 million doses in the first 100 days after he took office, a lower target than Trump’s plan, which Biden said would fail without intervention and new funding. Biden reiterated his proposal to ask all Americans to wear a mask for 100 days and make it mandatory on federal property and for interstate travel. At the same time, Trump was holding a vaccine summit at the White House, vowing to use executive powers if necessary to acquire sufficient doses. At the event, White House officials played videos of Biden and the government’s top infectious disease expert, Anthony Fauci, criticizing Trump’s pronouncement that the U.S. could develop a vaccine by year’s end. Biden introduced California Attorney General Xavier Becerra as his secretary of Health and Human Services, mispronouncing his name before apologizing and correcting himself. He also presented the other health officials that he had announced on Monday as he tries to stamp out the coronavirus pandemic, smoothly take over vaccine distribution and beef up the Affordable Care Act. The U.S. will emerge from the pandemic “stronger, more just and more equitable,” Becerra said via video. “It is our turn to build a nation where, as the president-elect so often says, health care is a right, not a privilege.” Biden’s vaccine pledge -- administering 100 million doses, which is enough for 50 million people, by end of April -- is less ambitious than the one Trump’s officials have laid out, though he argues it’s more realistic. Moncef Slaoui, a chief adviser to Trump’s Operation Warp Speed, said in a media call earlier this month that he thinks they would be able to distribute 200 million doses, enough to vaccinate 100 million people, by the end of February. “In the end of February, we will have potentially immunized a 100 million people,” Slaoui said. Biden is guaranteeing only 50 million people vaccinated between the inauguration and the end of April. He made clear that he believes Trump’s plan is on pace to stall. “There is a real chance that, after an early round of vaccinations, the effort will slow and stall,” Biden said, while calling on Congress to fund more distribution. “Developing the vaccine is one herculean task. Distributing it is another, and vaccines in a vial only work if they are injected into the arms of people, especially those most at risk.” Biden hasn’t announced his full health team, including a commissioner for the Food and Drug Administration, and may not get the ones he has unveiled. Becerra is facing a confirmation fight, with Republican senators raising questions about whether his experience as a congressman and California attorney general suits him for the health portfolio. Biden also picked Vivek Murthy for surgeon general while appointing Rochelle Walensky -- the infectious diseases chief at Massachusetts General Hospital -- as director of the Centers for Disease Control and Prevention and Marcella Nunez-Smith as COVID-19 Equity Task Force Chair. Nunez-Smith, Biden said, will ensure that low-income people and minorities, who are hit the hardest by the pandemic, receive fair treatment. Murthy said Tuesday that the U.S. health care system faced a host of problems beyond the coronavirus crisis, including addiction, mental health concerns, racial disparities and diabetes. Subscribe to our YouTube channel: https://bit.ly/2TwO8Gm Bloomberg Quicktake brings you live global news and original shows spanning business, technology, politics and culture. Make sense of the stories changing your business and your world. To watch complete coverage on Bloomberg Quicktake 24/7, visit http://www.bloomberg.com/qt/live, or watch on Apple TV, Roku, Samsung Smart TV, Fire TV and Android TV on the Bloomberg app. Have a story to tell? Fill out this survey for a chance to have it featured on Bloomberg Quicktake: https://cor.us/surveys/27AF30 Connect with us on… YouTube: https://www.youtube.com/user/Bloomberg Breaking News on YouTube: https://www.youtube.com/c/BloombergQuickTakeNews Twitter: https://twitter.com/quicktake Facebook: https://www.facebook.com/quicktake Instagram: https://www.instagram.com/quicktake