Middle East respiratory syndrome (MERS) has recently returned to the headlines as new cases have been exported to Korea and China. Experts are concerned that MERS cases continued to be detected in Saudi Arabia throughout the past year, and there appears to be little reduction in the number of cases since its first discovery three years ago. As the month of Ramadan approaches, with 1 million pilgrims expected to arrive in Saudi Arabia in June and July 2015, MERS remains a threat to global health security. The Lancet today publishes a new Seminar on MERS, outlining the current state of knowledge on the virus, and urgent priorities for research and control.
Seminar: Middle East respiratory syndrome, Zumla et al
Middle East respiratory syndrome (MERS) is a highly lethal respiratory disease caused by a novel single-stranded, positive-sense RNA betacoronavirus (MERS-CoV). Dromedary camels, hosts for MERS-CoV, are implicated in direct or indirect transmission to human beings, although the exact mode of transmission is unknown. The virus was first isolated from a patient who died from a severe respiratory illness in June, 2012, in Jeddah, Saudi Arabia. As of May 31, 2015, 1149 laboratory-confirmed cases (431 deaths; 38% mortality) have been reported to WHO. Both community acquired and hospital-acquired cases have been reported with little human-to-human transmission reported in the community. Although most cases of MERS have occurred in Saudi Arabia and the United Arab Emirates, cases have been reported in Europe, the USA, and Asia in people who travelled from the Middle East or their contacts. Clinical features of MERS range from asymptomatic or mild disease to acute respiratory distress syndrome and multiorgan failure resulting in death, especially in individuals with underlying comorbidities. No specific drug treatment exists for MERS and infection prevention and control measures are crucial to prevent spread in health-care facilities. MERS-CoV continues to be an endemic, low-level public health threat. However, the virus could mutate to have increased interhuman transmissibility, increasing its pandemic potential.