CNN

CNN's Anderson Cooper and Chief Medical Correspondent Sanjay Gupta speak to Mike Ryan, director of the World Health Organization's Health Emergencies Program about the US' capacity to test for the coronavirus and do contact tracing.

Learning from Italy: "I think other countries really, really need to step up and learn the lessons that are being learned in Italy right now. We have to push this virus back. It's not just enough to do social distancing. It's good to have that, it's great to separate people, but we have to be able to go after the virus," Ryan said.

Tailoring responses: "You've got 50 states. You've got a different situation in each of those states. And you need to tailor the responses in each of those states. And if you've got a chance you need to go after the virus. And contact tracing and isolation of cases is still a strategy that can be used," Ryan said.

Question on problems with testing in US: "If you don't test people, you don't know they're positive. Therefore, they may be positive and you don't have time to contact trace them because you don't know they have it," Cooper said.

Need to identify cases: "It's really important we identify all confirmed cases. We need to test suspected cases. We need those cases to be isolated, and it is difficult in a very intense environment. It's difficult to do the kind of detailed contact tracing. In Ebola, at the peak of the outbreak, we were tracing 25,000 contacts a day in the middle of a war zone. It is possible to do contact tracing even under the most difficult circumstances, but it does require a real scale-up in public health capacity. And where that can be done and the virus can be pushed back, we can save lives," Ryan said.