President Barack Obama said that the Ebola outbreak is a "national security threat" with "low margin for error" during extended remarks Wednesday afternoon in the White House's Roosevelt Room. Obama addressed the American public in a televised speech shortly after concluding a meeting with his senior health, homeland security and national security advisers that focused on the nation's response to Ebola.

"And so it is very important for us to make sure that we are treating this the same way that we would treat any other significant national security threat," he said. "And that’s why we’ve got an all-hands-on-deck approach -- from [the Department of Defense] to public health to our development assistance, our science teams -- everybody is putting in time and effort to make sure that we are addressing this as aggressively as possible."

Click play below to watch a video of the speech:

Obama spoke following news that two health care workers contracted the disease after treating Thomas Eric Duncan. When Duncan passed away on Oct. 8 at Texas Health Presbyterian Hospital Dallas, he became the first person to die of Ebola in America.

"We have learned some lessons, though, in terms of what happened in Dallas. We don’t have a lot of margin for error.  The procedures and protocols that are put in place must be followed," Obama said, referring to Duncan's death and the fact that the health care workers were infected.

"One of the things that we discussed today was how we could make sure that we’re spreading the word across hospitals, clinics, any place where a patient might first come in contact with a medical worker to make sure that they know what to look out for, and they’re putting in place the protocols and following those protocols strictly."

He went on to say that the U.S. -- which recently sent thousands of troops to West Africa to help with the fight against Ebola -- is dedicated to ending the outbreak in Guinea, Liberia and Sierra Leone, but that other countries need to more "aggressively" help in the effort.

"So the bottom line is, is that we’re doing everything that we can to make sure, number one, that the American people are safe; I’m confident that we’re going to be able to do that," he said. "But we’re also going to need to make sure that we stop this epidemic at its source."

He added that the U.S. government will look at "protocols to do additional passenger screening, both at the source and here in the United States" in order to stop the spread of Ebola via air travel.

The president's remarks came shortly after a Wednesday afternoon conference call led by the national nurses union National Nurses United that called attention to the severe lack of preparedness to treat Ebola patients and protect health care workers and the public from the deadly virus at hospitals across the United States.

National Nurses United Co-President Deborah Burger said on the call that health care workers who treated Duncan for days after he was admitted with Ebola "said there were no protocols ... There was no mandate for nurses to attend training, there was no advanced hands-on training for personal protective equipment ... The nurses feel untrained, unprepared and lied to." She called on President Barack Obama to declare a "mandate" to ensure proper protection protocols at all the nation's hospitals.