While the coronavirus is currently contained in the United States, the Centers for Disease Control and Prevention has said all Americans and American health care providers need to be prepared for that to change. With the virus spreading in Europe and the Middle East, the CDC believes it's now "more likely" that the disease could start spreading person-to-person within communities in the U.S., Principal Deputy Director Anne Schuchat said.

As of Wednesday, there were 58 confirmed cases of the COVID-19 disease caused by the new virus in the United States. Worldwide, more than 81,000 people have been infected, including almost 1,300 cases in South Korea, 374 cases in Italy and 139 cases in Iran. More than 2,700 people have died after getting the virus, but none in the United States.

Asked about the mixed messages from the CDC and the White House, which has downplayed the risk of the disease spreading, Schuchat acknowledged that it "can be a confusing time right now."

"The good news is that here in the United States the virus is contained. With an aggressive approach, we've been able to keep the numbers down," she said on "CBS This Morning" Wednesday. "But as we see outbreaks in Italy, in Iran, in South Korea, we need to be prepared in case things change here."

At a press conference on Tuesday, Schuchat warned that "it's not so much a question of if" an outbreak will happen, "but rather more a question of exactly when."

Schuchat said the CDC could not predict exactly where "community transmission" — significant spread between people in a specific geographic area — might pop up in the U.S., so they "need to be ready everywhere."

"We've seen in other outbreaks that there can be what's called a popcorn pattern, where one community has an outbreak and another doesn't. You can see that that's what's occurring in Italy right now," she said, noting that cases there were concentrated in two northern regions.

"We can't say for sure if we will get community transmission, but based on what we're seeing in Europe and the Middle East, we think it's more likely than we thought a week or two ago," she added.

Schuchat said there was an aggressive containment strategy at airports, and clinicians were working to detect the virus early in anyone coming to the U.S., as well as in people who may already be in the country.

"We've learned a lot in the last few weeks about the virus. It doesn't seem to be as severe as we first feared, but it does seem to be quite transmissible and some people have very mild symptoms or possibly even no symptoms at all," she said.

Schuchat also said the severe cases of the virus are "primarily occurring in the elderly, in adults with chronic conditions like diabetes or chronic lung disease.

"We haven't seen disease to any great extent in children, and that's a difference with seasonal flu or other influenza," she added. "One of the big drivers of our flu outbreaks each year is the high rates of illness in children, but we haven't seen that with this virus. It's something we're on the lookout for, but that hasn't been detected so far."