(CNN) -- Liberia's chief medical officer is on a 21-day Ebola quarantine after her assistant died from the illness, according to health officials. The assistant died Thursday, prompting the closure of the the Ministry of Health headquarters building for decontamination, officials said. The ministry reopened on Friday, but Dr. Bernice T. Dahn entered a quarantine period, her deputy, Tolbert Nyenswah, said. The assistant showed symptoms of Ebola 10 days ago, officials said, but Dahn last had contact with him 13 days ago. An American doctor who volunteered in Sierra Leone and was exposed to Ebola will be admitted to the Clinical Center of the National Institutes of Health in coming days, the NIH said in a statement.
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Liberia's chief medical official is in a quarantine, after her assistant died of Ebola
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Health Ministry closed for a day to decontaminate from Ebola
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A U.S. doctor who was exposed to Ebola in Sierra Leone will go to an NIH Clinic
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At least 6,553 cases of Ebola are reported in West Africa, WHO said
West Africa is fighting the worst Ebola outbreak on record, according to the @placeholder.