UPDATE: Thomas Duncan, the Ebola patient hospitalized in Dallas, died Wednesday morning, according to hospital officials. The original story is below.

The Centers for Disease Control and Prevention updated reporters on the man's condition in a briefing from its Atlanta headquarters Sunday. Duncan's status deteriorated from serious to critical over the weekend.

They say they are being bombarded by phone calls from other hospitals.

Atlanta's WSB-TV learned that the experimental drug used to help Ebola patients taken to Emory University Hospital is no longer available.

CDC officials say health care workers are doing everything possible to help Thomas Duncan and keep the virus from spreading.

Officials confirmed Sunday that Duncan took a turn for the worse while being treated at Texas Health Presbyterian Hospital in Dallas.

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Since the case was confirmed Tuesday, the CDC says the number of calls they are now dealing with has increased substantially.

“We were getting about 50 calls or emails per day before the initial patient was diagnosed; now it is up to about 800 per day,” CDC director Tom Frieden said.

On Friday, hazmat crews went to sanitize the apartment where Duncan and his family had been staying. Family members were moved to another location for monitoring, according to health officials.

Forty-eight others who came into contact with Duncan are also being monitored, officials said.

“Ebola only spreads with direct contact with someone who is sick,” Frieden said.

WSB-TV learned that Duncan will not be given the experimental drug Z-Map, which others, including the two patients in Atlanta, had been given.

“There were a very small number of those doses in the world and they are all gone,” health officials said.

With the increased calls to more heavily monitor international travel from the affected areas, the CDC’s director said:

“If we make it harder to fight the outbreak in West Africa, we actually increase our own risk.”

There is another experimental drug, but Frieden said it can make patients worse at first, so it will be up to the patient’s family and doctors to decide whether to treat the patient with it.