Ebola

CDC adds 76 to Ebola watchlist, regrets not sending big team

New Ebola cases could soon hit 10K per week, officials warn
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New Ebola cases could soon hit 10K per week, officials warn

Seventy-six hospital workers who treated an Ebola patient who died in Dallas last week or dealt with his blood are now being "actively monitored" for signs of the virus after a nurse contracted the disease from the same patient, a top federal health official said Tuesday, as he expressed regret for not having responded more aggressively sooner.

They join 48 other people who had or may have had contact with Ebola victim Thomas Eric Duncan before the Liberian national was admitted to a Dallas hospital, as well as one person who had contact with nurse Nina Pham, 26, after she was infected, said Dr. Thomas Frieden, head of the federal Centers for Disease Control.

Frieden said that with the benefit of hindsight, CDC should have initially dispatched "a more robust hospital infection team" to Dallas when Duncan was diagnosed with Ebola there late last month, as opposed to after Pham's diagnosis, as he has now done.

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"I wish we had put a team like this on the ground the day the first patient was diagnosed. That might have prevented this infection" of Pham, he said.

Pham is the first person to contract Ebola while in the United States. What caused her infection remains unknown, but the fact that it happened at all has lead CDC to "rethink" the way it tries to control Ebola from spreading to care-givers, Frieden has said.

"We should have put an even larger team on the ground immediately, we will do that from now on whenever there's a confirmed case," Frieden said during a briefing from CDC headquarters in Atlanta Tuesday. Such a team has been sent in the past two days to Texas Health Presbyterian Hospital in Dallas to augment another CDC team that was already in place there, he said.

"We've sent CDC's most experienced staff, people who have worked on Ebola outbreaks for decades, people who have stopped Ebola outbreaks ... in Africa," Frieden said.

"Most importantly," Frieden said, he has ordered that there be a "site manager" around the clock overseeing infection control efforts in Texas Presbyterian during Pham's treatment there.

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That manager and their team is "looking at every step in the procedure" of how health-care workers are treating Pham and how they are putting on and taking off protective garb, Frieden said. Two nurses who dealt with the recent Ebola cases of Dr. Kent Brantly and Nancy Writebol are being sent to Dallas, he said. Both Brantly and Writebol survived.

"Secondly, we're enhancing training" in how to identify people with Ebola and how to deal with suspected cases, he said.

Hard to tell if Ebola vaccine works: Pro
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Hard to tell if Ebola vaccine works: Pro

Frieden also said that CDC is recommending reducing the number of staff members who have interactions with Pham so that the remaining people become "more familiar and more systematic in how they put on and take off safety equipment."

Read MoreCDC must 'rethink' its approach to Ebola: Official

"We are looking at everything we can do to minimize this risk," Frieden said. "We know that a single breach can cause an infection."

Every hospital worker in the U.S. should know how to screen for Ebola, which includes asking patients if they have a fever, and if they have been in West Africa in the past month, particularly in the three countries that are the center of the current outbreak: Liberia, Sierra Leone and Guinea, he said.

Pham gets transfusion from Brantly

Pham is in stable condition while receiving treatment, and has received a plasma transfusion from Brantly, who survived the virus after treatment recently.

Read MoreEbola survivor donates blood plasma to nurse Nina Pham

Brantly previously donated blood to Dr. Rick Sacra, who survived the virus, as well as to Ashoka Mukpo, a freelance NBC News cameraman who is undergoing treatment for Ebola in a Nebraska hospital. That blood-based treatment is based on the theory that Ebola antibodies in Brantly's blood will help others combat the virus in their own bodies.

In a statement released by Texas Health Presbyterian on Tuesday, Pham said: "I'm doing well and want to thank everyone for their kind wishes and prayers. I am blessed by the support of family and friends and am blessed to be cared for by the best team of doctors and nurses in the world here at Texas Health Presbyterian Hospital Dallas."

10,000 new cases per week in West Africa

International health officials earlier Tuesday warned that Ebola could infect as many as 10,000 new people per week in West Africa by December, as those officials also emphasized the need for a bigger response to the deadly virus.

That projection is much higher than the current estimate of Ebola cases released Tuesday: 8,914 patients.

World Health Organization officials said the death toll from Ebola has hit 4,447.

"A lot more people will die" without increased efforts to combat Ebola, said Dr. Bruce Aylward, assistant director-general of WHO.

Zuckerberg donates $25 million to Ebola fight

Shortly after he spoke, Facebook founder Mark Zuckerberg revealed that he had donated $25 million as a grant to the Centers for Disease Control Foundation to help Ebola containment and treatment efforts.

Read MoreMark Zuckerberg donates $25 million to fight Ebola

Aylward said Ebola is now affecting more districts, counties and prefectures in Liberia, Sierra Leone and Guinea. Officials also said that the disease, in a troubling sign, is spreading to areas near the borders of those countries, raising the possibility that the virus will start affecting other nations on a larger scale.

WHO's projection of 10,000 new cases per week represents a tenfold increase in the current rate.

"We will go over 9,000 cases this week," Aylward said.

Ebola concerns deepen
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Ebola concerns deepen

The mortality rate of the current Ebola outbreak—the largest since the virus was discovered in the mid-1970s—is 70 percent, officials said.

President Barack Obama told the military chiefs of 20 countries Tuesday that "the world as a whole is not doing enough'' to stop Ebola from spreading. But Obama also said that it is very unlikely that the virus would become epidemic in the United State because of the quality of its health-care system.

A clinic in Leipzig, Germany, on Thursday confirmed that a 56-year-old male U.N. worker stricken with Ebola after working in Liberia had died, four days after being transferred to Germany.

In Kansas City, Kansas, officials said a man hospitalized there with a fever after serving as a medical officer on a ship off the coast of western Africa had tested negative for Ebola.

In Sierra Leone, an entire battalion of 800 soldiers from that nation was placed in quarantine after one of them tested positive for Ebola. The battalion had been scheduled to soon travel to Somalia to relieve a group of peacekeepers there.

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