About 50 Under Observation in Texas over Ebola

Those who may have had contact with traveler from Liberia

Health officials in Dallas charged with checking the spread of Ebola have narrowed their focus to about 50 people who had direct or indirect contact with an infected Liberian traveler, including 10 at high risk who are being checked twice daily for symptoms.

A cleanup crew began decontaminating the Dallas apartment where the man, Thomas Eric Duncan, had been staying before he was admitted to the hospital five days ago and where he remained in serious condition on Friday.

Four people close to Duncan, "will remain in the apartment during this time and it is safe for them to do so," Dallas County said in a statement. The four are quarantined in the apartment in a northeastern section of the city.