At least six states have issued tougher rules for travelers returning from Ebola-affected regions, some with mandatory quarantines going above and beyond federal guidelines.
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The moves are controversial and have sent politicians backpedaling and lawyers reading between the lines.
What are states doing?
A day after New York doctor Craig Spencer was diagnosed with Ebola after traveling home from treating Ebola patients in West Africa, the governors of New York and New Jersey announced that they would enforce mandatory quarantines for all travelers who had close contact with Ebola-infected people and were arriving from Guinea, Liberia and Sierra Leone -- the three countries hardest hit by the current epidemic.
Later the same day, Illinois Department of Public Health also announced a mandatory 21-day home quarantine for high-risk individuals who cared for Ebola patients in the same countries.
"This protective measure is too important to be voluntary," Illinois Gov. Pat Quinn said in a statement. "We must take every step necessary to ensure the people of Illinois are protected from potential exposure to the Ebola virus. While we have no confirmed cases of the Ebola virus in Illinois, we will continue to take every safeguard necessary to protect first responders, healthcare workers and the people of Illinois."
Late Sunday night, the governors of New York and New Jersey stressed that they would allow home quarantines with twice-daily monitoring from health officials. New York Gov. Andrew Cuomo said mandatory hospital quarantines would only be required of high-risk individuals arriving to New York and New Jersey who are not from either of those states.
Florida, Maine, Maryland and Virginia also announced tougher rules for travelers returning from Ebola-affected regions with the possibility of home quarantine.
Have they quarantined anyone yet?
Yes. On Friday, nurse Kaci Hickox was returning from Sierra Leone, where she had been treating Ebola patients, when she was detained and interrogated at Newark Liberty International Airport in New Jersey. She had no symptoms but was held against her will until today, when they announced they would release her.
Hickox detailed her ordeal in an Op-Ed for the Dallas Morning News, describing how she was held for 6 hours at the airport as she was treated "like a criminal."
In a text message this morning, she told ABC News Chief Health and Medical Editor Dr. Richard Besser, "I'm so thankful for the immense attention and support I've received. I just hope this nightmare of mine and the fight that I've undertaken is not in vain!"
Hickox has tested negative for the virus twice but was held in a quarantine tent at University Hospital in Newark anyway. Her lawyer argued that her basic human rights were being violated.
She will be released today to return home to Maine, where officials said they will require her to be under quarantine with active monitoring for the remainder of the 21 days -- the incubation period for Ebola.
Why are the quarantines controversial?
It doesn't mesh with Centers for Disease Control and Prevention guidelines, which assume that someone isn't contagious until Ebola symptoms appear. And even then, transmission requires contact with bodily fluids like blood and vomit.
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said Sunday on ABC News' "This Week" that "As a scientist and as a health person, if I were asked, I would not have recommended [mandatory quarantines]."
What are the federal rules?
The CDC announced on Oct. 22 that all airline passengers traveling from Ebola-affected nations would get Ebola kits and be required to self-monitor for 21 days, which is the maximum length of time it takes someone exposed to the virus to show symptoms. They are required to take their temperature twice daily and answer several questions about their symptoms, according to the CDC. If they do not report, they will be tracked down, the agency said.
Under CDC rules, doctors returning from treating Ebola patients in West Africa need to monitor their symptoms for 21 days, not quarantine themselves. Doctors Without Borders has similar guidelines.
"Self-quarantine is neither warranted nor recommended when a person is not displaying Ebola-like symptoms," Doctors Without Borders said Thursday in a statement. "However, returned staff members are discouraged from returning to work during the 21-day period."
Are the quarantines legal?
Public health lawyer Wendy Mariner, who teaches at Boston University School of Law, said the legalities of the quarantines depend on the laws in the states mandating them. In New York, the 9/11 attacks prompted the creation of stronger laws, allowing for people to be detained "even if they only might have been exposed to someone who might be sick," she said.
"That's a pretty broad determination, which, to my knowledge, has not been challenged," she said, adding that her colleagues think it's not an issue of the public panicking -- it's an issue of politicians panicking in an election year.
Still she said that if President Barack Obama wanted to formally declare the quarantines a national security issue, he could override the states. She said because they relate to borders, it is a federal matter.
Northwestern University professor of constitutional law Eugene Kontorovich disagreed, saying that state officials have the right to keep possibly-infected individuals from moving around their territories.
"The president is not doing that and not going to do that for political reasons," Kontorovich said. "Overriding quarantines puts it all on him if it doesn't work out."
Mariner said she thinks the quarantines are problematic -- and could become a federal matter -- because they will discourage health workers from traveling to West Africa to stop the Ebola outbreak at its source.
"It's a little odd to single them out," she said, adding that health workers are more likely to want to keep from spreading the disease they've been fighting and more likely to recognize the symptoms. "If you single out anyone who works with Ebola then you probably have to quarantine U.S. health care workers and U.S. hospital workers treating Ebola patients."
Do these quarantines violate the constitution?
Since the United States has a history of upholding quarantines, Kontorovich said the states have the right to enforce quarantines beyond the CDC guidelines. He said states wouldn't be able to impose a quarantine for the common cold, but because Ebola is a fatal disease with no cure, strict quarantines are permissible.
Kontorovich said Hickox's situation reminded him of a 1963 case in which a woman returning from Europe was isolated because she had traveled to a town in the midst of a smallpox outbreak. The woman, despite taking the matter to court, was quarantined for 14 days upon her return to New York even though she wasn't sick.
The states get to decide how they want to protect their citizens, he noted, and don't have to be conservative to do so. The greater good of the state outweighs the individual's freedoms for three weeks, he said, adding that he's glad New York has announced that it will be compensating the people it quarantines.
State governments can either be too strict and sacrifice a handful of people's freedom for 21 days or be too lax and allow people to become infected, he said. As a result, it would rather err on the side of caution.
"Once people are infected, you can't make them healthy, you can't put them back in the box," he said.
Self-monitoring assumes people will be compliant, he said, but there's no need for states to trust that this will happen.
"Your neighbors are not required to trust you," Kontorovich said.