Federal officials tightened screening measures at all airports on Wednesday, requiring agents to monitor arriving travelers for "general signs of illness." Travelers from West Africa would get their temperatures checked and answer questionnaires.
The Coast Guard, however, is not mandating screening for passengers and crew members arriving by sea. Instead, ships that docked at an Ebola hot spot in their past five port calls must answer a series of Ebola-related questions before entering a U.S. port, according to a notice on Monday from the Long Island Sound Coast Guard sector, which covers areas in New York and Connecticut.
But is this memo sufficient to prevent the risk of Ebola entering the U.S. via sailors? After all, more than 2,500 commercial ships with thousands of crew members enter and leave U.S. ports every day, according to the Coast Guard.
Although the questionnaire notice was issued by a New York metro sector, this procedure will be followed by all ships arriving in any U.S. port, according to Lt. Joe Klinker, a Coast Guard spokesman.
"The port's watch stander will speak directly with the vessel through radio or phone," Klinker said. "The ship will stay offshore until deemed safe—all decisions will be made with the Centers for Disease Control."
Questions include the number of persons presenting symptoms, whether medical treatment has been administered and when the symptoms started.
Since it takes several weeks to cross the ocean from Africa, it makes sense that screening measures differ between airplanes and ships, said Douglas Stevenson, director of the Center for Seafarers' Rights at the Seamen's Church Institute.
"If someone had the Ebola virus on a ship, symptoms will appear long before he arrives in the U.S. But in the airplane, you could have someone who's just in the early stages of the symptoms," Stevenson said.
Scott Bergeron, CEO of the Liberian International Ship and Corporate Registry (LISCR), agreed with Stevenson.
"Employment contracts are normally six weeks or longer and this, coupled with voyage transit times of two to four weeks ... provide for a monitoring of seafarers health during the average Ebola incubation period prior to a ship's arrival in the U.S," Bergeron said in an email.
Ebola symptoms appear from two to 21 days after exposure, according to the CDC.
After Panama, Liberia, a West African nation, has the second-largest open flag registry in the world. International law requires all vessels to be registered by a country—and flagged. The LISCR, based in Virginia, administers all Liberian flags.
But just because a ship flies a Liberian flag does not mean it has a Liberian or West African crew, Bergeron said. Therefore, the prevalence of Liberian flags does not exacerbate the spread of Ebola-carrying passengers.
"Liberia specifically ... is not a significant provider of seafarers to the international shipping industry," he said. "The international laws regarding crew onboard ships focus on competency and training and not nationality ... as such, there are very few Liberian and African seafarers employed on merchant ships."
Regardless of which flag a ship flies, the Coast Guard will be monitoring all ships using the same procedures, said Klinker.
"We want to take steps that everyone is operating with a sense of heightened awareness and asking common sense questions for inbound vessels," Klinker said.
"It's a competitive advantage to have a well-run flag because you don't want your ship detained," Stevenson said. "It's not in the ship's interest for their crew to get sick with this. So, they'll take any guidance issued very seriously."