The Middle East Respiratory Syndrome—How Worried Should We Be?

Perlman, Stanley

One year after the first case was identified, the total number of MERS cases remains low, with fewer than 100 cases reported. However, this is no reason for complacency. First, the virus has already spread from Saudi Arabia to Europe and is likely to spread throughout the world as infected patients travel for medical and other reasons. Second, human-to-human transmission, initially considered to be a minor component of the disease process, has been documented in family and hospital settings. Early reports suggested that virus spread primarily to patients with underlying medical conditions, but recent documentation of spread to healthy persons, including health care workers, means that wider populations are at risk. This is a particular concern in Saudi Arabia, which is both the primary site of MERS infection and the destination for the Hajj, the yearly pilgrimage in which several million Muslims travel to Mecca. Last year's Hajj did not result in an increase in MERS cases, and it is some comfort that Mecca is located across the country from the governorate of Al-Ahsa. However, large numbers of individuals will again make the Hajj this year in mid-October, a scenario that creates a substantial risk for widespread infection.