Monday, 5 October 2015

A place to be critical...

Around May/June 2015, the Middle East respiratory syndrome (MERS) coronavirus escaped its Arabian Peninsula bonds and exploded...still associated with the circumstances created under lax hospital conditions...into another part of the world entirely - South Korea.

About 20% of South Korean MERS cases were fatal. In contrast, nearly twice that proportion have died after MERS-CoV infection among 26 countries (36% fatal).[1] Meanwhile, a little over twice the SOuth Korea proportion of fatal cases occurs in the Kingdom of Saudi Arabia (KSA; 42%).[2] 

It is interesting to look at another possible measure of clinical impact - how often a MERS patient is publicly described via official channels as being in "critical" condition. I suspect that this term could be applied as arbitrarily as anything else used by humans, nonetheless, see the figure below.

Total MERS-CoV detections (mustard bars; left-hand axis)
and mentions of cases in "critical" condition (red bars; right-hand axis).
Taken from the MERS-CoV data visualizations page.[3]
Click on image to enlarge.
A few things:

  • Sadly, you have to ignore the biggest peak - the Jeddah-2014 hospital outbreak (March to June) - as data during that time were rare and detail was mostly absent both from the KSA Ministry of Health and the World Health Organization
  • If we look at the South Korea peak (May/June 2015) versus the most recent Riyadh outbreak (July/August 2015), there seem to be a lot more mentions of critical cases. There is also more red visible during the Eastern Region/Ar Riyadh region peak around January/February 2015. 
There may be little to conclude from observations such as this, but it is yet another interesting pattern to muse upon.  

Older males with comorbidities are heavily represented among MERS disease cases that present to hospitals (younger people among those with mild or no notable disease) and older  males and females with comorbidities among the fatal outcomes. A shared risk is that comorbidities are preyed upon by MERS-CoV.

Comorbidities include diabetes mellitus, cirrhosis and various lung, renal and cardiac conditions. All of these are diseases of concern among countries with abundant unhealthy food options, weight issues and ageing populations. Is your country one of those? Even familiar old viruses could re-emerge as threats to this subgroup as the years go by. In the meantime, emerging newly identified viruses create an atmosphere of concern.

MERS-CoV detections broken down by age bands and into total cases
(left hand graphs), and those with a fatal outcome (ri
ght-hand grpahs).
Taken from the MERS-CoV data visualizations page.[3]
Click on image to enlarge.


References..
  1. http://www.who.int/csr/don/01-october-2015-mers-jordan/en/
  2. http://www.moh.gov.sa/en/CCC/PressReleases/Pages/Statistics-2015-10-04-001.aspx
  3. http://virologydownunder.blogspot.com.au/2014/08/mers-cov-daily-monthly-and-cumulative.html