Starting Wednesday, travelers who have spent time in Liberia, Sierra Leone, and Guinea will have to land in one of five airports if they want to gain access to the US, reports USA Today. The Department of Homeland Security announced today that all travelers coming from Ebola-stricken countries will have to go through enhanced screening — screening that currently only takes place in New York City, Chicago, Newark, Washington, and Atlanta.

"We are working closely with the airlines to implement these restrictions with minimal travel disruption," said Jeh Johnson, secretary of Homeland Security. "If not already handled by the airlines, the few impacted travelers should contact the airlines for rebooking, as needed."

Enhanced screening procedures began on October 11th at John F. Kennedy Airport in New York. Chicago’s O’Hare International Airport, Atlanta’s Hartsfield-Jackson International Airport, Washington's Dulles International Airport, and Newark’s Liberty International Airport later followed suit. The screening procedure consists of taking a traveler’s temperature using a thermometer that doesn’t require skin contact. In addition, customs personnel ask about travel history, and look for symptoms of the disease.

These precautions stop short of a travel ban — a measure that is becoming increasingly popular among certain politicians. A travel ban would likely make the outbreak in West Africa even worse because it would spread panic and cause more people to become infected, scientists say. Controlling the outbreak in Africa would therefore become even harder.

At present, the US does not have an Ebola outbreak. Two nurses in Dallas were diagnosed with Ebola after treating Thomas Duncan, a now-deceased Liberian citizen who travelled to the US to visit family members.

So far, the Ebola outbreak has been concentrated in three African countries: Liberia, Sierra Leone and Guinea. Since the beginning of the outbreak, about 9,200 have been infected, and more than 4,500 have died from the disease. Ebola can be controlled through routine hand-washing, and by using gloves and other barriers to prevent contact with infectious bodily fluids, like blood and vomit. Ebola isn’t airborne. It spreads through direct contact with the body fluids of a person who is showing symptoms of Ebola.