NEW YORK - U.S. health officials are recommending that people who are at highest risk for coming down with Ebola avoid commercial travel or attending large public gatherings, even if they have no symptoms.
The Centers for Disease Control and Prevention issued the updated advice to state and local officials on Monday.
The CDC guidance comes after the governors of New York and New Jersey announced mandatory quarantines for medical workers returning from three West African countries plagued by the worst Ebola outbreak in world history. Illinois and Maryland have announced quarantines for health workers at high risk for getting the disease, including anyone who's touched an Ebola patient's body fluids without protective gear.
CBS News chief medical correspondent Dr. Jon LaPook said Monday's new CDC guidelines defines "high risk" as someone who has known exposure to the virus. For example, a family member who cared for someone with Ebola, or someone with a needle stick from an infected patient.
If that patient has no symptoms, the CDC recommends daily monitoring by a health official for 21 days and restrictions that prohibit travel by airplane, ship, or long-distance bus or train, said LaPook.
Previously the CDC has recommended screening of travelers from West Africa and monitoring of people for three weeks after they arrive in the United States.
On Monday, the CDC broke down people in the orbit of Ebola into four categories. Those at highest risk are anyone who's had direct contact with an Ebola patient's body fluids, including health care workers who suffer a needle-stick injury during a patient's care.
For those people who are at highest risk and asymptomatic, the CDC recommended restrictions on commercial travel or attendance at public gatherings. The guidelines were not specific about where a person should stay, but officials said they meant home or hospital isolation.
For those with some risk, like who lived in a household with an Ebola patient but didn't have direct contact, travel restriction can be decided on a case-by-case basis, government officials said.
In announcing the guidance Monday, CDC Director Dr. Tom Frieden said he worried some of the announced state policies "have the effect of creating stigma or false impressions."
Experts say infected people only spread the disease when they are suffering symptoms, like fever, vomiting and diarrhea. They say mandatory quarantines of those without symptoms are unnecessarily severe and will discourage health workers from going to West Africa to fight the epidemic.
Policy debates about Ebola patients escalated late last week, when Dr. Craig Spencer, a 33-year-old emergency room doctor, came down with Ebola symptoms several days after returning to New York City from medical aid work in Guinea. Before he developed symptoms, he rode the subway, went bowling and did other activities around town.
New York Mayor Bill de Blasio said Monday that Spencer's condition remains serious but stable. No infection has been found in his fiancee but she remains under quarantine at the couple's Harlem home. No one else has been reported as infected, and city health officials said New Yorkers should not be alarmed about contracting the disease.
More than 4,900 Ebola deaths have been reported this year during the current epidemic, nearly all of them in Guinea, Liberia and Sierra Leone.