A child on the plane developed a fever during the flight and was hospitalized with a parent in isolation pending testing for the coronavirus. Staff from the Centers for Disease Control and Prevention, the Department of Health and Human Services and the Administration for Children and Families are at the military bases to assist the passengers.
"We do not believe these people pose a threat in the location they'll be held," said Dr. Nancy Messonnier, director of the CDC's National Center for Respiratory Diseases.
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Dr. Henry Walke, director of the CDC's Division of Preparedness and Emerging Infections, said at a news conference at Travis AFB that it was a "very emotional experience" to see the passengers arrive after the 11-hour flight from China.
"There was applause," Walke said. "They're glad to be here. They've been through a lot. And because of the unknown nature of this coronavirus, there's uncertainty. And that creates some stress, as well."
Several more planes from Wuhan are expected to arrive at Marine Corps Air Station Miramar in San Diego, Lackland Air Force Base in San Antonio and Eppley Airfield in Omaha, Nebraska.
A dozen patients
The evacuations come as the 12th case of the coronavirus in the U.S. was confirmed Wednesday, this time in Wisconsin.
Few details of the 12 U.S. patients have been given as health officials walk the line between patient privacy and duty to public health. But Wednesday, the CDC released a bit more information about the first 11 cases.
The majority — eight — are men. All are adults: Four are in their 20s or their 30s, one is over 40 and six are in their 50s or their 60s.
Nine of the 11 had traveled to China; the two others caught the virus from a spouse in the U.S. According to the CDC, all 11 appear to be doing well, including two in San Benito, California, who previously needed more intensive care.
While it's clear that the virus can spread from people who have symptoms, such as fever, cough and breathing difficulties, many questions remain about the transmission.
A new report from Chinese health authorities suggested that it may be possible for a pregnant woman to pass the virus to her unborn child. The CDC, however, questioned that theory.
"It would be pretty unusual" for a respiratory virus to spread in that manner, Messonnier said. "I've heard of no similar reports from other countries."
What's more, the CDC said more information is needed to determine whether an asymptomatic patient — that is, a person who's been exposed but hasn't become ill — can spread the virus.
Coroanaviruses are "thought to spread mainly through droplets from coughs or sneezes, similar to influenza," Walke said.
Also Wednesday, the World Health Organization announced that it is asking the global community for $675 million in aid to help control the spread of the coronavirus.
"Our message to the international community is invest today or pay more later," WHO's director-general, Dr. Tedros Adhanom Ghebreyesus, said at a briefing in Geneva.
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The Bill and Melinda Gates Foundation said it is donating up to $100 million "to improve detection, isolation and treatment efforts; protect at-risk populations in Africa and South Asia; and accelerate the development of vaccines, drugs and diagnostics."
In the U.S., the CDC is the only entity able to test for the new coronavirus. That is expected to change in the coming days and weeks, because the CDC has been able to develop test kits to send to public health labs nationwide.
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