Friday, 18 September 2015

MERS by month, camel and mass gathering...

I haven't updated this figure in a long while but recently had the chance to add some new camel calving season data [1] and another festival to my earlier lists [2-4] - the Um Ragaiba festival.[6] 

The Um Ragaiba festival is purportedly the largest of the human|camel gatherings, located north of Riyadh and near Buraidah and Hafr Al-Batin - interestingly, are all sites of infamy among the tales told in MERSville.[5]

MERS-CoV detection in humans by month. Also showing spring and
summer seasons in the Kingdom of Saudi Arabia and some key
camel and festival dates.
Click on image to enlarge
The latest version of this figure highlights a few things to me:
  1. I don't see a seasonality here which is not surprising. Most human cases are due to human error creating the circumstances by which health care related outbreaks take off. These happen at different times. It is hard to remove that very loud noise and see if a seasonality remains. A seasonality that is presumably due to times when there are more active camel infections increasing the risk of human infections through proximity and direct contact with infected hosts
  2. The Kingdom of Saudi Arabia has at last taken the threat posed by MERS-CoV infected camels seriously. In 2015, two big festivals which had camel involvement, Janadriyah and Um Ragaiba were not held. Take note China and avian influenza
  3. The bulk of human cases occur within a timeframe bracketed by camel calving season - so, keeping in mind what I said above, rather than season, perhaps we can agree that the period in which higher numbers of MERS-CoV cases occur, seems to be in the Arabian Peninsula's spring and summer - even if that outbreak is in South Korea! When virus activity rises at the source, so does the risk of death and significant economic and social impact beyond the borders of that source