BETHESDA, MD. (WJZ)– As an American with Ebola continues to receive treatment at a Maryland hospital Saturday night–the Centers for Disease Control and Prevention says at least 10 more Americans are on their way home after possibly being exposed to the deadly disease in West Africa.

The aid worker arrived at the National Institutes of Health in Bethesda Friday, in serious condition — from Sierra Leone.

The CDC says the 10 Americans returning to the U.S. may have been exposed to bola, but so far are not showing any symptoms of the disease.

The World Health Organization estimates the Ebola outbreak has killed more than 10-thousand people.