MERS-CoV jumps a flight to South Korea...but from where?

It could be Qatar, Bahrain, the United Arab Emirates (UAE) or the Kingdom of Saudi Arabia (KSA). Any of these may have been the country of origin for the infected person who returned with a bunch of microscopic passengers, to the 24th country to host a case of Middle East respiratory syndrome coronavirus (MERS-CoV) infection - South Korea. 

The infected man then passed the spiky parasites on to his 63-year old wife and to a 76-year old man with whom he shared his hospital room. Close contact. From what we know of the MERS-CoV - it's a pretty ineffective transmitter among us humans types, preferring instead to give the hump to dromedaries.

Qatar seem less likely as it appears to have only been an airport transit point. If it's Bahrain, then we have 25 countries as Bahrain has not yet reported a MERS-CoV positive person. Both the people and the camels of the UAE and KSA are well known to this virus both in humans and camels. 

We await the clarity of the World Health Organization's analysis in a Disease Outbreak News (DON) article - although this might be a tough one to unravel.

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