The Airbus was operating flight BA564 destined for Milan.
Over the weekend, the Italian authorities imposed quarantine orders for 10 small towns near the city.
Molly Hunter of NBC News tweeted: “At #Heathrow, our BA #Milan flight is delayed.
“The captain just announced there are passengers (I count 3) on board who don’t want to travel due to #coronavirus.
“Already pushed back... now re-attaching.”
The plane finally left 20 minutes behind schedule.
The airline later said a single passenger had decided to leave the aircraft.
A British Airways spokesperson said: “As with all our customers, we will always respect their wishes if they change their mind about flying at the last minute. The flight left within a few minutes of its scheduled departure time.”
The decision by the passenger appears bizarre, since they had already gone through the most dangerous part of the journey in terms of infection.
International airports are bio-hazard rich environments, and Heathrow is busier than any other in Europe.
There is no Foreign Office warning against visiting Milan or other Italian cities.
On Twitter, “Ploubezre” responded: “Why did they even board the plane in the first place, if they don’t want to travel?”
BA will absorb the costs of the delay, though the passengers involved will lose their fare and any subsequent flights on the same itinerary.
Separately, the Foreign Office has warned travellers to North Korea: “Foreigners who have travelled into North Korea from virus-affected countries are subject to a 30 day period of quarantine and medical supervision.”
The warning is largely immaterial since links from China have been suspended, and there are no other entry points.
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