Carnival Cruise Lines in America and Crystal Cruises have added a question about Ebola to their medical screening questionnaires as the Carnival Magic reported passengers had disembarked “smoothly” at its Galveston homeport.

The Magic was hit by health scare reports last week when it was reported a nurse who may have processed samples of the deadly disease was on board.

Public health personnel conducted a screening of the lab worker before the disembarkation and a blood test confirmed she was not infected.

The woman and her husband drove themselves home after leaving the ship.

‘There is no evidence of a public health threat to cruise passengers or to Galveston County,’ a Galveston County Health Authority was reported as saying.

Carnival told reporters it was undertaking an “aggressive” cleaning and sanitising process, even though health authorities were making no specific orders about hygiene on the ship.

The line maintained it was mainly for the reassurance of passengers.

Last week’s events point up the problems of major disease scares like Ebola for the cruise industry, and may cause many lines to review their screening methods.

The woman passenger had confined herself to her cabin and self monitored last week. The ship’s doctor had also examined her.

Medical screening questionnaires are given to passengers on arrival for a cruise covering past travel locations and touch points.

This week, the Carnival and Crystal added a question about contact with anyone diagnosed with Ebola. Anyone answering in the affirmative could be denied access to the ship.

The initiative was in accordance with a Cruise Line International Association’s (CLIA) recommendation.