As many as ten people in the Seattle area and Connecticut, many of whom arrived recently from West Africa, are the latest in the United States being watched for Ebola symptoms.
So far, none of them has displayed any signs of the deadly virus, authorities and reports say.
The Seattle Times reports, and CBS Seattle affiliate KIRO-TV confirms, that a nurse in the Seattle area is being monitored and is voluntarily restricting her movements to minimize any possible risk to others.
Dr. Jeff Duchin, communicable-disease chief for Public Health -- Seattle King-County, told the newspaper the nurse came back to the U.S. from Africa, where she had treated patients with Ebola.
She will be monitored through the disease's 21-day incubation period, the newspaper says.
In West Haven, Connecticut, health officials have quarantined a family of six, all of whose members arrived in the U.S. on Oct. 18 from one of the Ebola-affected countries in West Africa, Mayor Edward M. O'Brien's office says.
All are staying with friends and have been quarantined as a precaution, West Haven Health Director Maureen B. Lillis adds.
The 21-day quarantine is being supervised by the West Haven Police Department.
The mayor's office says they're being watched to comply with an Oct. 7 order by Gov. Dannel Malloy in which he declared a public health emergency in the state.
The New York Times quotes a spokesman for Connecticut's Public Health Department, William Gerrish, as saying three Yale University students are also being monitored and have been told to stay home.
Officials told the newspaper the quarantining of all nine was voluntary, and none had objected to it.
Under a new policy announced Wednesday by the Centers for Disease Control and Prevention, all travelers who come into the U.S. from three Ebola-stricken West African nations will be monitored for three weeks. It's the latest step by federal officials to keep the disease from spreading into the U.S.
Starting on Monday, anyone traveling from Guinea, Liberia and Sierra Leone will have to report in with health officials daily and take their temperature twice a day.
The measure applies not only to visitors from those countries but also returning American aid workers, federal health employees and journalists.
The virus has killed more than 4,800 people in West Africa, nearly all in Liberia, Sierra Leone and Guinea.