Outbreak in South Korea is described as "large and complex."
Eight new cases of the deadly virus were announced in South Korea.
The World Health Organization predicts more cases in the country, where MERS has already claimed two lives.
Ebola has a high mortality rate, but in the right conditions its rate of infection can be kept low.
The rate of infection has slowed since mid-May, which public health officials say may be a result of improved infection control procedures introduced in Saudi hospitals
The patient contracted the virus overseas and brought it to America, the CDC said
Saudi officials on Saturday said the rate of infections was on the rise, with the total number of cases hitting 396
“We expected MERS-CoV to make its way to the U.S. We have been preparing for this," an official said