Middle East Respiratory Syndrome: Emergence of a Pathogenic Human Coronavirus

Abstract

In 2012, a zoonotic coronavirus was identified as the causative agent of Middle East respiratory syndrome and was named MERS coronavirus (MERS-CoV). As of August 11, 2016, the virus has infected 1,791 patients, with a mortality rate of 35.6%. Although MERS-CoV generally causes subclinical or mild disease, infection can result in serious outcomes, including acute respiratory distress syndrome and multi-organ failure in patients with comorbidities. The virus is endemic in camels in the Arabian Peninsula and Africa and thus poses a consistent threat of frequent reintroduction into human populations. Disease prevalence will increase substantially if the virus mutates to increase human-to-human transmissibility. No therapeutics or vaccines are approved for MERS; thus, development of novel therapies is needed. Further, since many MERS cases are acquired in healthcare settings, public health measures and scrupulous attention to infection control are required to prevent additional MERS outbreaks.

Keywords: animal models; antiviral therapies; camels; host–virus interactions; immune response; outbreak.

Figure 1

Case distribution of MERS-CoV in Saudi Arabia, 2013–2016. The total (A) and percentage (B) of primary, secondary, or unknown MERS cases are plotted per year in Saudi Arabia. While secondary cases of MERS predominated during the early stages of the outbreak, improved infection and healthcare controls have significantly reduced the number and percentage of secondary cases in the last two years (13; 81).