Saturday, March 03, 2018

More MERS Murmurs From Saudi Arabia


For reasons that are not exactly clear, over the past month the Saudi MOH's daily posting of MERS-CoV reports has become increasingly erratic, with more than half the days of February going unreported (see list below), along with discrepancies between the Arabic and English language reports

Edited Screenshot 3/3/18 - Only 12 days in February Reported

As of this writing we've not seen an official update in six days, but hopefully we'll see one with some back-filling of data soon. 
But what we do have is a media report appearing (virtually verbatim) in a number of Arabic language newspapers this morning - with comments attributed to the Undersecretary of the MOH - announcing an escalating number of MERS-CoV cases across the country. 
Aside from the announced (unquantified) escalation in MERS cases, we also have what appears to be a rare public acknowledgment of the risk of asymptomatic transmission of the virus.

Although media reports must always be taken with a grain of salt, a (translated) example of this morning's media reports (bolding mine) follows, after which I'll return with more.

Health": "Corona" at the height of its activity .. and we recorded a surge in cases
14:22 - 03/03/2018
Hail Net - rebounds:  Undersecretary of the Ministry of Health for Preventive Health Dr. Abdullah Asiri revealed a surge in cases of infection with "Corona" Middle East respiratory syndrome.

Said Asiri The virus is currently witnessing the peak of its activity, indicating according to the newspaper "Riyadh" that a number of health facilities in the Kingdom recorded an increase in cases, and that it will continue until the end of March.

He added that the increased disease usually occurs at the time of the transition between the seasons, stressing the need to avoid contact with camels during this period of being in the secretion of the live virus, and not to go to the markets of camels and slaughterhouses without taking preventive measures.

He explained that a person with the virus may not show symptoms if good health, and may transmit the virus to his contacts who have nothing to do with camels, and they may suffer from the actual symptoms of the disease

If today's media reports can be taken at face value (always a big `if')  then we are missing a substantial number of case reports for February (January saw 25 cases & 8 deaths reported).
More interesting, however, is the statement in the last paragraph warning of asymptomatic transmission of the virus.
Up until the summer of 2015, the Saudis treated `asymptomatic' RT-PCR positive cases (usually discovered while contract testing during a hospital outbreak) as something `less' than a MERS case.
They were rarely reported, and were not included in their MERS statistics.
That is until the World Health Organization issued a particularly strong rebuke (without singling out the Saudis) in their WHO Statement On The 10th Meeting Of the IHR Emergency Committee On MERS, stating:
The Committee further noted that its advice has not been completely followed. Asymptomatic cases that have tested positive for the virus are not always being reported as required.
Timely sharing of detailed information of public health importance, including from research studies conducted in the affected countries, and virological surveillance, remains limited and has fallen short of expectations.
Inadequate progress has been made, for example, in understanding how the virus is transmitted from animals to people, and between people, in a variety of settings. The Committee was disappointed at the lack of information from the animal sector.
Since then, we've seen a substantial jump in the number of `asymptomatic' (or perhaps, mildly symptomatic) cases reported out of Saudi Arabia.  As discussed previously, there remain serious questions over how one defines  `symptomatic’. 
Are `sniffles’ considered symptomatic?  Malaise?  Is there a specific fever threshold?   Are non-respiratory symptoms (gastrointestinal) counted?
While most large outbreaks have occurred in health care facilities (and to a lesser extent, households), we see a substantial number of sporadic community acquired cases with no known high risk (camel, medical facility, or patient) exposure.
Some are classified as having  `indirect camel exposure' (generally being in contact with a healthy person with recent camel contact)  and we've seen household members of apparently healthy health care workers infected. 
But most `primary' cases seem to become infected without any obvious route of exposure. Which is why sporadic community transmission from unidentified mildly ill or asymptomatic carriers keeps coming up as a possibility.
We saw a 2016 study (see EID Journal: Estimation of Severe MERS Cases in the Middle East, 2012–2016) suggesting that as much as 60% severe of Saudi MERS cases go undiagnosed. A 2013 study published in The Lancet Infectious Diseases, that estimated for every case identified, there are likely 5 to 10 that go undetected.
While still not appearing to be ready  for prime time (see Study: A Pandemic Risk Assessment Of MERS-CoV In Saudi Arabia) - the MERS-CoV virus continues to evolve - and we are far from understanding exactly how it is transmitting, and possibly sustaining itself, in the Middle Eastern community.

Which means that today's murmurs on MERS are worth our attention.

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