Tracing the path of 'patient zero'

Eight days after returning from a business trip to the Middle East, a 68-year-old man in South Korea developed a cough and fever.

He visited four health facilities seeking treatment and inadvertently triggered the biggest outbreak of Middle East respiratory syndrome outside that region - and what is verging on national panic at home.

The businessman, known as "patient zero", was running a farm-equipment company in Bahrain, according to a South Korean official, and had visited the region before returning on May 4.