Monica Villamizar:

At first, the medical teams fighting Ebola were simply caught in the crossfire, but now they are targets.

This past year, the World Health Organization counts nearly 400 attacks on treatment units and health workers. The week we arrived, violent street protests forced a lockdown at the U.N. base that is the nerve center of the Ebola response.

So, for now, we're stuck. And it's not just us. The doctors, the medical detectives, and the vaccination teams are trapped here as well.

The cafeteria has been turned into a makeshift office for all the medical professionals you see here. They're on lockdown, and that is a problem, they say, because, if they can't go out, they can't monitor who has Ebola and who may be spreading it to other people.

The next day, we head north.

We are hearing that the protesters are armed and increasingly hostile towards the U.N. and health workers, so we're being evacuated from Butembo. We're going to Beni, a city that's also on lockdown. And we're being escorted by the police.

The city of Beni, with a population a quarter-million, has been at the center of the outbreak. The number of cases is down from its peak in the spring, but a deteriorating security situation makes it very hard to stamp out the final viral flames.

And just as in Butembo, there are growing protests. This protest leader says they're angry that U.N. troops are not doing more to stop the violence, and says the foreign doctors must leave.