Passengers on a British Airways flight from Riyadh to London on April 24 were contacted by Public Health England after a suspected case of the Mers respiratory virus.
The passengers on BA flight 262 from the Saudi Arabian capital to America via London Heathrow were told they should call the NHS 111 service immediately if they were sitting near a passenger with the virus, who has now been admitted to a hospital in the States.
According to ITV News, Public Health England said the risk of infection was "extremely low" but was contacting the passengers "as a precautionary measure."
The BBC reports that the infected man is believed to be a health care worker from Saudi Arabia, who stopped at Heathrow before travelling to Chicago.
Public Health England said that Mers has an incubation period of up to 14 days, so any illness starting after 9 May would not be related.
Last November, a French jet was quarantined at an airport near Toulouse after passengers showed symptoms of the H1N1 virus, commonly known as swine flu.
The low-cost Hop flight, a subsidiary of Air France, landed at Blagnac airport from Nice with 47 passengers coughing and spluttering, while others developing signs of fever.
According to The Local, one French newspaper said the scene started to "resemble something out of a disaster movie".
Concerned French authorities decided to quarantine the plane on the runway when it arrived at Blagnac airport.
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