A Muslim pilgrim performing evening prayers in Mecca's Grand Mosque during this year's hajj pilgrimage. Health officials in Saudi Arabia have been on high alert amid growing concerns over the deadly MERS coronavirus. (Fayez Nureldine/AFP)
Oman is now the latest country to join the list of nations impacted by the coronavirus that causes MERS, or Middle East respiratory syndrome.
The Omani patient is a 68-year-old man from the Al Dahkliya region who became sick on Saturday and was in hospital by Monday. So far, it does not seem as though he has recently travelled outside of the country.
The three Saudi cases - two men and a woman, one of them a health care worker - are between 49 and 83 and all had underlying medical conditions. None appear to have had any contact with animals, but health officials are still looking into it.
The WHO says it has now recorded 149 MERS cases, confirmed by lab testing, 63 of which were fatal. There are likely even more cases, however, if you include those where lab confirmations weren't possible. An excellent list can be found here at FluTrackers, an online community of people interested in infectious disease news.
And like every MERS update, this one doesn't answer the biggest question of all: what is the source of MERS and how are people getting infected? The likeliest animal source is still probably the bat (which, as of yesterday, is a proven source of coronaviruses) - but how the virus is getting from these animals into humans is still anyone's guess.