leaving aside the well documented instances of infectious diseases being rapidly transmitted from country to country by the agency of the ubiquitous plane , these are now so commonplace as almost to be regarded as a habitual risk of travel , and the names - sars , ebola , rixs-2 - no longer evoke the same terror that they once did , but consider , if you will , just the terminology of the airport buildings , and you will see that any would-be traveller of the skies , has a perfect right to feel afraid .