British health officials have issued advice to passengers after a suspected case of the Mers respiratory virus on board a flight passing through London. Public Health England said a passenger on BA flight 262 from Riyadh, who passed through Heathrow on 24 April, had been admitted to a US hospital. People sitting near the passenger have been contacted and anyone else feeling unwell should call the NHS 111 service. Public Health England said the risk of infection was "extremely low". Saudi Arabia has said more than 100 people infected with Mers - short for Middle East respiratory syndrome - have died since an outbreak began in 2012. Mers causes fever, pneumonia and kidney failure. The infected man, believed to be a health care worker from Saudi Arabia, stopped at Heathrow before travelling on to Chicago. No cases of Mers in the UK have been detected since February 2013, Public Health England said. The infection is a coronavirus, a large family of viruses that also includes the common cold and Sars (severe acute respiratory syndrome).