Correlation Between UpToDate Searches and Reported Cases of Middle East Respiratory Syndrome During Outbreaks in Saudi Arabia

Thorner, Anna R.; Cao, Bin; Jiang, Terrence; Warner, Amy J.; Bonis, Peter A.

For a control group, we analyzed UpToDate searches in 4 control cities in Saudi Arabia that were not having MERS outbreaks at the time that the Jeddah and Riyadh outbreaks were occurring in 2014; the control cities were Abha, Buraydah, Medina, and Tabuk. We selected these cities to be the 4 control cities because they did not have MERS outbreaks at the time of 2014 outbreaks in Jeddah and Riyadh and because the combined search volume of UpToDate searches in these cities was similar to the search volume in Jeddah during the same period. To establish a baseline for the Jeddah and Riyadh outbreaks in 2014, data were selected from January 1, 2014 to February 28, 2014 (considered an outbreak-free period). We calculated the mean and standard deviation for the baseline periods.