As a physician, sociologist, and former hospice doctor, Nicholas A. Christakis is in a unique position to understand COVID-19 and its ripple effects on society. His latest book explores what it means to live amid a plague, and he speaks to Hari Sreenivasan about all this and more – including what he thinks President-elect Biden must do to restore confidence in institutions.

Early data announced by Moderna today indicates that its coronavirus vaccine is 94.5% effective--just one week after Pfizer shared the successful early results of its own trials. This news couldn’t come at a more critical time, as infections increase at unprecedented speed. CNN Senior Medical Correspondent Elizabeth Cohen outlines the differences between Moderna and Pfizer's vaccines.

Jon Ossoff is the Democratic Senate candidate in Georgia's runoff election against sitting GOP Senator David Perdue, and if he were to win – along with fellow Democrat Raphael Warnock – in January, it would flip the senate from Republican to Democrat. Ossoff joins the program to discuss the stakes.

Europe's top heads of state have now congratulated President-elect Biden, hoping to refresh transatlantic alliance ties after four years of tension with the U.S. Stability is of paramount concern for France in particular. Today marks five years since deadly terrorist attacks in Paris with more attacks in recent weeks.All this as the country faces a second wave of COVID-19 and economic devastation.

Conspiracy theories and misinformation about coronavirus and the recent election are spreading like wildfire online. These are the sort of phenomena Renée DiResta has been studying for years. She is a disinformation expert and technical research manager at the Stanford Internet Observatory, and she speaks with Hari Sreenivasan about what can happen when false narratives go viral.

Novelist Chimamanda Ngozi Adichie, who is reviewing President Obama's upcoming memoir for the New York Times, is perhaps best known for her novels "Americanah" and "Half of a Yellow Sun." The latter book was just crowned the "winner of winners" of the Women’s Prize for Fiction. She joins the program from Lagos, Nigeria to reflect on Obama, her own literary success, and a year of racial reckoning.

A world of challenges lie ahead for President-elect Joe Biden's administration--challenges made more difficult as President Trump removes top staffers at the Pentagon. The president has begun the process of stacking the Department of Defense and other government agencies with political allies. Christiane is joined by Ambassador James Jeffrey.

As President Trump continues to battle the election results, we turn for insight to his niece Mary Trump, a clinical psychologist. Her recent bestselling book "Too Much and Never Enough" tells the story of her childhood and how President Trump came to despise the concept of losing.

Records numbers of COVID-19 patients are entering hospitals across the country for the second day in a row. Epidemiologist Michael Osterholm, an expert in infectious disease and public health, has been named to President-elect Biden's COVID-19 task force. He speaks with Walter Isaacson about building community trust in vaccines.

Secretaries of state around the nation -- Republican and Democrat alike -- say there has been no evidence of meaningful voter fraud. Yet President Trump still has not recognized President-elect Biden's victory. Democratic Senator Chris Coons, who has been a close friend of President-elect Biden for many years, joins the program to discuss.

What separates President Trump’s behavior from that of the average autocrat? Masha Gessen is a Russian-American journalist who has been writing about authoritarianism for decades. Their latest book, "Surviving Autocracy," makes the case that Trump’s presidency has endangered American democracy and the world’s faith in it. Gessen speaks with Michel Martin about all this--and about the road ahead.

From Europe to India, world leaders are congratulating President-elect Joe Biden on his victory. UK Prime Minister Boris Johnson had found common cause with President Trump over Brexit, but now says he is looking forward to working closely with Biden on issues like climate change. To discuss the world's reaction to this unusual election, Christiane speaks with former Prime Minister Tony Blair.

One of the surprises of this election was President Trump’s strong performance with Latinx voters. Initial exit polls show that Trump’s share increased four percentage points since 2016. Journalists Paola and Jorge Ramos know the community well. Paola is the author of "Finding Latinx," and her father Jorge is a renowned news anchor for Univision, America's leading Spanish-language network.

The media played a vital role during the Trump presidency. During this election, watchers around the world were intently following the vote count. How has President Trump changed the media landscape? Ben Smith is media columnist for The New York Times. He tells Walter Isaacson about the current state of traditional media outlets, and the impact on newsrooms of the Black Lives Matter movement.

President Trump refuses to concede the election and is trying his best to leverage lawsuits and muster media support. Barry Richard was a lawyer for George W. Bush during his infamous recount battle with Vice President Al Gore--a case that made it all the way to the Supreme Court. Richard joins Christiane to offer his perspective on Trump's legal battles.

In her first TV address since the election, German Chancellor Angela Merkel congratulated Biden and Harris. Celebrating the end of Trump's "America first and only" doctrine, Merkel called on the U.S. and the EU to stand together to "master the major challenges of our time." Joining Christiane to discuss this is former EU foreign policy chief and former Italian Foreign Minister Federica Mogherini.

Early data shows that a COVID-19 vaccine developed by pharmaceutical company Pfizer is more than 90% effective. Although still in trials, Pfizer believes as many as 50 million doses could be made available this year. Rep. Pramila Jayapal just won her third term in Congress, and healthcare was one of the main focuses of her platform. She joins Christiane to discuss this and react to the election.

For the most part, elected Republicans are rallying around President Trump’s refusal to admit defeat, with only a handful condemning Trump’s actions or congratulating President-elect Biden. Newsmax Media is also refusing to accept the reality of the election outcome. Christiane speaks with Chris Ruddy, the organization’s CEO and a close confidant of Trump.

Rep. James Clyburn (D-SC) helped change the course of history by endorsing Biden and bringing out the Black vote in his state at a critical moment. This made possible Biden's big win in South Carolina, propelling him to secure the nomination – and the presidency. Clyburn joins Christiane to react to Biden's presidential win.

After a month-long spike, there are now over 10 million coronavirus cases in the U.S. and over 50 million globally. Despite these statistics, news of a promising vaccine is being greeted with cautious optimism. Christiane discusses the latest with Hugh Montgomery, chair of the National Emergency COVID Critical Care Committee.