Cruisers who may have come in contact with Ebola will be banned from boarding a ship, as part of a new policy designed to reduce a potential outbreak at sea.

The move comes less than a week after an Ebola scare aboard Carnival Magic. A nurse who had handled Ebola specimens fell ill on the ship during a Caribbean cruise.

The passenger put herself in voluntary confinement and took a blood test. The test later confirmed she did not have the virus.

Despite the false alarm, the ship was unable to dock at Belize and Mexico.

Industry body, Cruise Lines International Association (CLIA) has since urged all its members to adopt new protocols to reduce the risk of Ebola at sea.

Protocols include denying boarding to those who have travelled to affected countries within 21 days of embarkation.

A statement from CLIA Australasia said: “CLIA and its member cruise lines have worked diligently and in conjunction with public health authorities to develop and distribute to all cruise line members strong protocols, and additional guidance, to reduce even further the already low risk of Ebola on a cruise ship.”

Carnival was the first to adhere to the advice, adding a question about the virus to its medical questionnaires.

Crystal Cruises has added two questions and said any embarking guest, visitor or crew that answers yes will be denied from boarding the ship.

Crystal’s questions are:

– Have you been to or travelled through Liberia, Sierra Leone or Guinea within the past 30 days?

– Within the past 30 days did you, or any person in your party, have physical contact with, or help care for (including lab work), someone diagnosed with or suspected to have Ebola?

Carnival Australia told Cruise Passenger in an email that the line has “robust medical protocols in place” that meet Australian and international recommendations.

“In keeping with this approach, we have added some questions to the mandatory pre-boarding health questionnaire that guests customarily complete,” a statement from the line read.

And Royal Caribbean says it too has added a question regarding travel to affected countries and the line will scan passports for stamps and visas from those destinations.

Any guest or crew member that has visited affected countries in the past 30 days will not be permitted to board.

“Royal Caribbean is reaching out to future guests with passports or mailing addresses in the affected areas before they travel to the ship,” a spokesperson said in a statement to Cruise Passenger.

“Royal Caribbean is closely monitoring the situation and following guidance from such health experts as the World Health Organization (WHO) and the US Centers for Disease Control and Prevention (CDC).”