Democratic debate: Latest news and analysis after Bernie Sanders and Joe Biden battle in first one-on-one showdown

Biden correctly notes that the US turned down a World Health Organization test for the coronavirus.

Biden says the US should "be planning where to put the temporary hospitals" as it did with a response to H1N1 and Ebola.

The current pandemic is exposing systemic issues in the existing infrastructure, Sanders argues.

While Biden argues that the crisis in Italy points to the failure of a single-payer system, Sanders says that in the US "the dysfunctionality in the system is obviously apparent".

"Clearly, we are not prepared," Sanders says.

This debate so far— no audience, a lot of room to get as close to nuance on a singular issue of healthcare — is the best opportunity yet for Sanders to make his care for Medicare for All.

Biden is forced to defend the current system.

After Sanders lays out the case for single-payer care and the pressure from the health lobby to prevent that kind of system, Biden says he doesn't want to get into a back-and-forth" on politics — which is the point of a debate.

"This is like a war", Biden says. One in which people wouldn't be billed for their care in the middle of a crisis, unrelated to the greater healthcare system and specific to the national emergency.

Biden, pointing to his bona fides as VP: "We have to lead the world ... in saying, 'This is what we must do.' We have to have a common plan. ... We need world leadership."

Sanders, asked to respond: "We have to act in an unprecedented way. ... It also means we tell the pharmaceutical companies and big money interests that this is not a time for profiteering."

On the Federal Reserve's recent interest rate cuts and liquid injection, Biden says to adjust the economy, we need a "major bailout package" that doesn't benefit corporations but individuals.

Sanders says the wealthy are likely to weather the crisis but the majority of Americans will be hardest hit. It's "unjust how so few have so much and so many have so little."

How the candidates are framing the coronavirus debate is crucial in understanding their perspective.

Biden is trying to reel the focus to the current crisis, taking a "first things first" approach. Sanders is making the case that the crisis is part of a larger systemic one.

These are fundamentally different ways of looking at the response and it's difficult for them to navigate past.

How are the candidates protecting themselves?

Sanders, though he loves rallies, is continuing his streaming remarks including a fireside chat and "using a lot of soap."

Biden is avoiding crowds and handshakes.

It's an understatement that their campaigns are dramatically changed in a crucial time due to the public health threat.

Biden is asked to argue against a political revolution.

 "We have problems we need to solve now. What's a revolution going to do, disrupt everything in the meantime?"

Couple of live fact-check callouts from Sanders.

Biden also denied having supported cuts to Social Security. Sanders is trying to give him an out: "You've been on the floor of the Senate time and time again" for cuts to social security and says he may have "changed your mind" on "but it doesn't change reality."

He went from denying it to explaining why he did.

The 1:1 format gives these men an opportunity to go tit-for-tat on their voting records.

On the Defense of Marriage Act, Hyde, Brady bill and the Iraq War.