After a couple of quiet days the Saudi MOH is reporting a new, `primary' MERS case from Buraidah; a 40 y.o. male in critical condition.
`Primary cases’ are those that occur in the community when there is no known exposure to a health care facility or to a known human case. Over the past 3 years, roughly 40% of Saudi cases are listed as either `primary’ or as from an undetermined origin.
Some primary cases may result from camel contact, although in this case we have no indication of that being a factor. MERS infection can sometimes produce mild or subclinical illness, so another possibility is there may be some limited `stealth’ transmission of the virus by unrecognized carriers in the community (see The Community Transmission Mystery).