British Airways fell more than nine per cent, while Thomas Cook and Thomson parent TUI Travel were also suffering from the fear of a full-blown pandemic, down five and three per cent respectively.
Fellow blue chip stock Carnival, the cruise operator, saw an eight per cent slide, while low-cost carrier easyJet dropped five per cent.
News of the Mexico flu and its rising death toll - more than 100 so far - also left the wider market lower.
It was a similar picture on Wall Street, as investors feared the flu could spread and thwart economic recovery, particularly in areas that rely on travel and tourism.
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