U.S. concerns have intensified after two nurses from the Dallas hospital who cared for Duncan contracted the virus, which has killed nearly 4,500 people, mostly in West Africa. President Barack Obama's administration is facing sharp criticism from lawmakers over its efforts to contain the disease at home.
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The employee has been self-monitoring since last Monday and has yet to develop a fever or show any other symptom of Ebola, the statement said. The worker and a companion voluntarily isolated themselves in their cabin, and U.S. officials are arranging for the ship to return to the country.
"We are working with the cruise line to safely bring them back to the United States out of an abundance of caution," Psaki said in the statement.
The person left the country before being notified of the U.S. Centers for Disease Control and Prevention's (CDC) updated requirement for active monitoring, the statement said.
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The Government of Belize said in a statement hours earlier that it had denied a request by U.S. officials to use a Belizean airport to transport a cruise ship passenger considered to be a very low risk for Ebola.
"The passenger never set foot in Belize," the statement said. "When even the smallest doubt remains, we will ensure the health and safety of the Belizean people."
The maximum incubation window for the disease is 21 days, according to the CDC.
On Friday, Carnival Cruise Lines issued the following statement:
Late afternoon on Wednesday, Oct. 15., we were made aware by the U.S. CDC of a guest sailing thisweek on board Carnival Magic who is a lab supervisor at Texas HealthPresbyterian Hospital. At no point in time has the individual exhibitedany symptoms or signs of infection and it has been 19 days since she was in thelab with the testing samples. She is deemed by CDC to be very low risk. At this time, the guest remains in isolation on board the ship and is notdeemed to be a risk to any guests or crew. It is important to reiterate thatthe individual has no symptoms and has been isolated in an extreme abundance ofcaution. We are in close contact with the CDC and at this time it has beendetermined that the appropriate course of action is to simply keep the guest inisolation on board.
None of Carnival Cruise Lines' ships visit the region where Ebola cases areoriginating nor do our ships call in any countries with Level 3 CDC TravelHeath Notices. Any passengers or crew who have visited or traveledthrough Liberia, Sierra Leone and Guinea within 21 days of a cruise departuredate will be denied boarding. Additionally, all guests sailing with us mustanswer a series of health screening questions during embarkation and, if deemednecessary, will be asked to submit to further medical screening prior to beingallowed to board. All cruise lines continue to monitor the situation closely,along with our colleagues in the rest of the travel industry. The cruise industry is in close, frequent contact with the U.S. Centers for DiseaseControl and Prevention (CDC) and the World Health Organization (WHO) for updates and guidance. Carnival Magic is based year-round in Galveston, TX and operates seven-day cruises to the Caribbean. The ship departed Galveston on Sunday, Oct. 12 and will return on Sunday, Oct. 19.