The legality of the Obama administration’s plans to screen certain airline passengers for Ebola has been questioned, but public health experts say the president has the U.S. Constitution on his side. Federal law allows authorities to quarantine people coming into the country who may pose a risk of spreading certain infectious diseases. The list of diseases for which travelers can be quarantined includes cholera, smallpox, plague and viral hemorrhagic fever, which Ebola falls under. Any attempt to fight the airport screenings in court, experts say, would be unsuccessful, the Associated Press reports.  

"You are subject to an entrance screening per the laws of the land," Rebecca Katz, an associate professor of public health policy at George Washington University, told the AP. The 1944 Public Health Service Act gives authority to the federal government to take steps to prevent the transmission of infectious diseases into the U.S. or across state borders. "You can choose not to be screened, but then you don't get to come into the country,” Katz said.

The ongoing Ebola outbreak in West Africa has sparked fears of a possible U.S. spread. Thomas Eric Duncan, who was diagnosed with the virus while in the U.S. and died this week at a hospital in Dallas, came to America from Liberia with Ebola before his symptoms occurred. Had Duncan registered a fever at the airport in Liberia, where authorities there have stepped up their own health screenings to weed out travelers who may carry the virus, he probably would have been pulled aside for further testing.

Triaging -- separating people who may be ill from those who aren't -- can be tricky, especially since Ebola can incubate in the human body for up to 21 days before symptoms, including fever, occur. Symptoms of Ebola --– vomiting, muscle aches and headache -- also look a lot like other viruses, including Typhoid fever and malaria, both of which are endemic to Africa and far more common than Ebola.

The U.S. will begin screening travelers arriving at five of the country’s busiest airports for signs of Ebola infection. Passengers coming from Liberia, Sierra Leone and Guinea will have their temperatures taken by agents upon arrival and answer a series of health-related questions, including whether they had any contact with an Ebola patient in West Africa. Screenings could start as early as this weekend for the 150 or so travelers who come from those countries and fly to the U.S. every day. The airports where screenings will take place are Kennedy International in New York, Washington Dulles International in Virginia, O’Hare International in Illinois, Hartsfield-Jackson International in Georgia and Newark Liberty International in New Jersey.