Two days ago the Saudi MOH reported a primary MERS case (camel contact) in Hufoof, which was the site of a large nosocomial outbreak in the summer of 2015.
Today they are reporting a secondary case in a female Health Care Worker. The HCW is described as being `asymptomatic', and was likely detected via routine testing of contacts.
Last month, in EID Journal: Estimation of Severe MERS Cases in the Middle East, 2012–2016, we saw an analysis that suggested 60% of symptomatic cases likely go undiagnosed.
Like most viral infections, MERS-CoV can also produce a wide range of illness, and so it is likely that many mild or asymptomatic cases go undetected as well.
Earlier this summer we saw a large nosocomial outbreak (see Saudi MOH On KKUH MERS Outbreak & Increased Asymptomatic Detections) in Riyadh, which involved at least 28 patients, 21 of whom were asymptomatic.
While KSA has done a much better job in 2016 in limiting hospital acquired outbreaks, we'll be watching the events in Hufoof closely over the next few days, to see if the Saudis detect any further spread of the virus.